Downgrade rust-toolchain.toml

DO NOT MERGE

.github/scripts/update-dev-builder-version.sh

@@ -0,0 +1,37 @@
+#!/bin/bash
+
+DEV_BUILDER_IMAGE_TAG=$1
+
+update_dev_builder_version() {
+  if [ -z "$DEV_BUILDER_IMAGE_TAG" ]; then
+    echo "Error: Should specify the dev-builder image tag" 
+    exit 1
+  fi
+
+  # Configure Git configs.
+  git config --global user.email greptimedb-ci@greptime.com
+  git config --global user.name greptimedb-ci
+
+  # Checkout a new branch.
+  BRANCH_NAME="ci/update-dev-builder-$(date +%Y%m%d%H%M%S)"
+  git checkout -b $BRANCH_NAME
+
+  # Update the dev-builder image tag in the Makefile.
+  gsed -i "s/DEV_BUILDER_IMAGE_TAG ?=.*/DEV_BUILDER_IMAGE_TAG ?= ${DEV_BUILDER_IMAGE_TAG}/g" Makefile
+
+  # Commit the changes.
+  git add Makefile
+  git commit -m "ci: update dev-builder image tag"
+  git push origin $BRANCH_NAME
+
+  # Create a Pull Request.
+  gh pr create \
+      --title "ci: update dev-builder image tag" \
+      --body "This PR updates the dev-builder image tag" \
+      --base main \
+      --head $BRANCH_NAME \
+      --reviewer zyy17 \
+      --reviewer daviderli614
+}
+
+update_dev_builder_version

.github/workflows/release-dev-builder-images.yaml

@@ -24,11 +24,19 @@ on:
         description: Release dev-builder-android image
         required: false
         default: false
+      update_dev_builder_image_tag:
+        type: boolean
+        description: Update the DEV_BUILDER_IMAGE_TAG in Makefile and create a PR
+        required: false
+        default: false
 
 jobs:
   release-dev-builder-images:
     name: Release dev builder images
-    if: ${{ inputs.release_dev_builder_ubuntu_image || inputs.release_dev_builder_centos_image || inputs.release_dev_builder_android_image }} # Only manually trigger this job.
+    # The jobs are triggered by the following events:
+    # 1. Manually triggered workflow_dispatch event
+    # 2. Push event when the PR that modifies the `rust-toolchain.toml` or `docker/dev-builder/**` is merged to main
+    if: ${{ github.event_name == 'push' || inputs.release_dev_builder_ubuntu_image || inputs.release_dev_builder_centos_image || inputs.release_dev_builder_android_image }}
     runs-on: ubuntu-latest
     outputs:
       version: ${{ steps.set-version.outputs.version }}
@@ -57,9 +65,9 @@ jobs:
           version: ${{ env.VERSION }}
           dockerhub-image-registry-username: ${{ secrets.DOCKERHUB_USERNAME }}
           dockerhub-image-registry-token: ${{ secrets.DOCKERHUB_TOKEN }}
-          build-dev-builder-ubuntu: ${{ inputs.release_dev_builder_ubuntu_image }}
-          build-dev-builder-centos: ${{ inputs.release_dev_builder_centos_image }}
-          build-dev-builder-android: ${{ inputs.release_dev_builder_android_image }}
+          build-dev-builder-ubuntu: ${{ inputs.release_dev_builder_ubuntu_image || github.event_name == 'push' }}
+          build-dev-builder-centos: ${{ inputs.release_dev_builder_centos_image || github.event_name == 'push' }}
+          build-dev-builder-android: ${{ inputs.release_dev_builder_android_image || github.event_name == 'push' }}
 
   release-dev-builder-images-ecr:
     name: Release dev builder images to AWS ECR
@@ -85,7 +93,7 @@ jobs:
 
       - name: Push dev-builder-ubuntu image
         shell: bash
-        if: ${{ inputs.release_dev_builder_ubuntu_image }}
+        if: ${{ inputs.release_dev_builder_ubuntu_image || github.event_name == 'push' }}
         env:
           IMAGE_VERSION: ${{ needs.release-dev-builder-images.outputs.version }}
           IMAGE_NAMESPACE: ${{ vars.IMAGE_NAMESPACE }}
@@ -106,7 +114,7 @@ jobs:
 
       - name: Push dev-builder-centos image
         shell: bash
-        if: ${{ inputs.release_dev_builder_centos_image }}
+        if: ${{ inputs.release_dev_builder_centos_image || github.event_name == 'push' }}
         env:
           IMAGE_VERSION: ${{ needs.release-dev-builder-images.outputs.version }}
           IMAGE_NAMESPACE: ${{ vars.IMAGE_NAMESPACE }}
@@ -127,7 +135,7 @@ jobs:
 
       - name: Push dev-builder-android image
         shell: bash
-        if: ${{ inputs.release_dev_builder_android_image }}
+        if: ${{ inputs.release_dev_builder_android_image || github.event_name == 'push' }}
         env:
           IMAGE_VERSION: ${{ needs.release-dev-builder-images.outputs.version }}
           IMAGE_NAMESPACE: ${{ vars.IMAGE_NAMESPACE }}
@@ -162,7 +170,7 @@ jobs:
 
       - name: Push dev-builder-ubuntu image
         shell: bash
-        if: ${{ inputs.release_dev_builder_ubuntu_image }}
+        if: ${{ inputs.release_dev_builder_ubuntu_image || github.event_name == 'push' }}
         env:
           IMAGE_VERSION: ${{ needs.release-dev-builder-images.outputs.version }}
           IMAGE_NAMESPACE: ${{ vars.IMAGE_NAMESPACE }}
@@ -176,7 +184,7 @@ jobs:
 
       - name: Push dev-builder-centos image
         shell: bash
-        if: ${{ inputs.release_dev_builder_centos_image }}
+        if: ${{ inputs.release_dev_builder_centos_image || github.event_name == 'push' }}
         env:
           IMAGE_VERSION: ${{ needs.release-dev-builder-images.outputs.version }}
           IMAGE_NAMESPACE: ${{ vars.IMAGE_NAMESPACE }}
@@ -190,7 +198,7 @@ jobs:
 
       - name: Push dev-builder-android image
         shell: bash
-        if: ${{ inputs.release_dev_builder_android_image }}
+        if: ${{ inputs.release_dev_builder_android_image || github.event_name == 'push' }}
         env:
           IMAGE_VERSION: ${{ needs.release-dev-builder-images.outputs.version }}
           IMAGE_NAMESPACE: ${{ vars.IMAGE_NAMESPACE }}
@@ -201,3 +209,24 @@ jobs:
             quay.io/skopeo/stable:latest \
             copy -a docker://docker.io/$IMAGE_NAMESPACE/dev-builder-android:$IMAGE_VERSION \
             docker://$ACR_IMAGE_REGISTRY/$IMAGE_NAMESPACE/dev-builder-android:$IMAGE_VERSION
+  
+  update-dev-builder-image-tag:
+    name: Update dev-builder image tag
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+      pull-requests: write
+    if: ${{ github.event_name == 'push' || inputs.update_dev_builder_image_tag }}
+    needs: [
+      release-dev-builder-images
+    ]
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Update dev-builder image tag
+        shell: bash
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          ./.github/scripts/update-dev-builder-version.sh ${{ needs.release-dev-builder-images.outputs.version }}

Cargo.toml

@@ -163,7 +163,7 @@ paste = "1.0"
 pin-project = "1.0"
 prometheus = { version = "0.13.3", features = ["process"] }
 promql-parser = { version = "0.5.1", features = ["ser"] }
-prost = "0.13"
+prost = { version = "0.13", features = ["no-recursion-limit"] }
 raft-engine = { version = "0.4.1", default-features = false }
 rand = "0.9"
 ratelimit = "0.10"

Makefile

@@ -8,7 +8,7 @@ CARGO_BUILD_OPTS := --locked
 IMAGE_REGISTRY ?= docker.io
 IMAGE_NAMESPACE ?= greptime
 IMAGE_TAG ?= latest
-DEV_BUILDER_IMAGE_TAG ?= 2024-12-25-a71b93dd-20250305072908
+DEV_BUILDER_IMAGE_TAG ?= 2025-04-15-1a517ec8-20250428023155
 BUILDX_MULTI_PLATFORM_BUILD ?= false
 BUILDX_BUILDER_NAME ?= gtbuilder
 BASE_IMAGE ?= ubuntu

flake.lock

@@ -8,11 +8,11 @@
         "rust-analyzer-src": "rust-analyzer-src"
       },
       "locked": {
-        "lastModified": 1742452566,
-        "narHash": "sha256-sVuLDQ2UIWfXUBbctzrZrXM2X05YjX08K7XHMztt36E=",
+        "lastModified": 1745735608,
+        "narHash": "sha256-L0jzm815XBFfF2wCFmR+M1CF+beIEFj6SxlqVKF59Ec=",
         "owner": "nix-community",
         "repo": "fenix",
-        "rev": "7d9ba794daf5e8cc7ee728859bc688d8e26d5f06",
+        "rev": "c39a78eba6ed2a022cc3218db90d485077101496",
         "type": "github"
       },
       "original": {
@@ -41,11 +41,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1743576891,
-        "narHash": "sha256-vXiKURtntURybE6FMNFAVpRPr8+e8KoLPrYs9TGuAKc=",
+        "lastModified": 1745487689,
+        "narHash": "sha256-FQoi3R0NjQeBAsEOo49b5tbDPcJSMWc3QhhaIi9eddw=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "44a69ed688786e98a101f02b712c313f1ade37ab",
+        "rev": "5630cf13cceac06cefe9fc607e8dfa8fb342dde3",
         "type": "github"
       },
       "original": {
@@ -65,11 +65,11 @@
     "rust-analyzer-src": {
       "flake": false,
       "locked": {
-        "lastModified": 1742296961,
-        "narHash": "sha256-gCpvEQOrugHWLimD1wTFOJHagnSEP6VYBDspq96Idu0=",
+        "lastModified": 1745694049,
+        "narHash": "sha256-fxvRYH/tS7hGQeg9zCVh5RBcSWT+JGJet7RA8Ss+rC0=",
         "owner": "rust-lang",
         "repo": "rust-analyzer",
-        "rev": "15d87419f1a123d8f888d608129c3ce3ff8f13d4",
+        "rev": "d8887c0758bbd2d5f752d5bd405d4491e90e7ed6",
         "type": "github"
       },
       "original": {

flake.nix

@@ -21,7 +21,7 @@
         lib = nixpkgs.lib;
         rustToolchain = fenix.packages.${system}.fromToolchainName {
           name = (lib.importTOML ./rust-toolchain.toml).toolchain.channel;
-          sha256 = "sha256-i0Sh/ZFFsHlZ3oFZFc24qdk6Cd8Do8OPU4HJQsrKOeM=";
+          sha256 = "sha256-arzEYlWLGGYeOhECHpBxQd2joZ4rPKV3qLNnZ+eql6A=";
         };
       in
       {

rust-toolchain.toml

@@ -1,2 +1,2 @@
 [toolchain]
-channel = "nightly-2025-04-15"
+channel = "nightly-2024-12-25"

src/client/src/database.rs

@@ -36,8 +36,8 @@ use common_grpc::flight::{FlightDecoder, FlightMessage};
 use common_query::Output;
 use common_recordbatch::error::ExternalSnafu;
 use common_recordbatch::RecordBatchStreamWrapper;
-use common_telemetry::error;
 use common_telemetry::tracing_context::W3cTrace;
+use common_telemetry::{error, warn};
 use futures::future;
 use futures_util::{Stream, StreamExt, TryStreamExt};
 use prost::Message;
@@ -192,6 +192,36 @@ impl Database {
         from_grpc_response(response)
     }
 
+    /// Retry if connection fails, max_retries is the max number of retries, so the total wait time
+    /// is `max_retries * GRPC_CONN_TIMEOUT`
+    pub async fn handle_with_retry(&self, request: Request, max_retries: u32) -> Result<u32> {
+        let mut client = make_database_client(&self.client)?.inner;
+        let mut retries = 0;
+        let request = self.to_rpc_request(request);
+        loop {
+            let raw_response = client.handle(request.clone()).await;
+            match (raw_response, retries < max_retries) {
+                (Ok(resp), _) => return from_grpc_response(resp.into_inner()),
+                (Err(err), true) => {
+                    // determine if the error is retryable
+                    if is_grpc_retryable(&err) {
+                        // retry
+                        retries += 1;
+                        warn!("Retrying {} times with error = {:?}", retries, err);
+                        continue;
+                    }
+                }
+                (Err(err), false) => {
+                    error!(
+                        "Failed to send request to grpc handle after {} retries, error = {:?}",
+                        retries, err
+                    );
+                    return Err(err.into());
+                }
+            }
+        }
+    }
+
     #[inline]
     fn to_rpc_request(&self, request: Request) -> GreptimeRequest {
         GreptimeRequest {
@@ -368,6 +398,11 @@ impl Database {
     }
 }
 
+/// by grpc standard, only `Unavailable` is retryable, see: https://github.com/grpc/grpc/blob/master/doc/statuscodes.md#status-codes-and-their-use-in-grpc
+pub fn is_grpc_retryable(err: &tonic::Status) -> bool {
+    matches!(err.code(), tonic::Code::Unavailable)
+}
+
 #[derive(Default, Debug, Clone)]
 struct FlightContext {
     auth_header: Option<AuthHeader>,

src/cmd/src/metasrv.rs

@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+use std::fmt;
 use std::time::Duration;
 
 use async_trait::async_trait;
@@ -131,7 +132,7 @@ impl SubCommand {
     }
 }
 
-#[derive(Debug, Default, Parser)]
+#[derive(Default, Parser)]
 pub struct StartCommand {
     /// The address to bind the gRPC server.
     #[clap(long, alias = "bind-addr")]
@@ -171,6 +172,27 @@ pub struct StartCommand {
     backend: Option<BackendImpl>,
 }
 
+impl fmt::Debug for StartCommand {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct("StartCommand")
+            .field("rpc_bind_addr", &self.rpc_bind_addr)
+            .field("rpc_server_addr", &self.rpc_server_addr)
+            .field("store_addrs", &self.sanitize_store_addrs())
+            .field("config_file", &self.config_file)
+            .field("selector", &self.selector)
+            .field("use_memory_store", &self.use_memory_store)
+            .field("enable_region_failover", &self.enable_region_failover)
+            .field("http_addr", &self.http_addr)
+            .field("http_timeout", &self.http_timeout)
+            .field("env_prefix", &self.env_prefix)
+            .field("data_home", &self.data_home)
+            .field("store_key_prefix", &self.store_key_prefix)
+            .field("max_txn_ops", &self.max_txn_ops)
+            .field("backend", &self.backend)
+            .finish()
+    }
+}
+
 impl StartCommand {
     pub fn load_options(&self, global_options: &GlobalOptions) -> Result<MetasrvOptions> {
         let mut opts = MetasrvOptions::load_layered_options(
@@ -184,6 +206,15 @@ impl StartCommand {
         Ok(opts)
     }
 
+    fn sanitize_store_addrs(&self) -> Option<Vec<String>> {
+        self.store_addrs.as_ref().map(|addrs| {
+            addrs
+                .iter()
+                .map(|addr| common_meta::kv_backend::util::sanitize_connection_string(addr))
+                .collect()
+        })
+    }
+
     // The precedence order is: cli > config file > environment variables > default values.
     fn merge_with_cli_options(
         &self,

src/common/function/src/aggr.rs

@@ -19,4 +19,4 @@ mod uddsketch_state;
 pub use geo_path::{GeoPathAccumulator, GEO_PATH_NAME};
 pub(crate) use hll::HllStateType;
 pub use hll::{HllState, HLL_MERGE_NAME, HLL_NAME};
-pub use uddsketch_state::{UddSketchState, UDDSKETCH_STATE_NAME};
+pub use uddsketch_state::{UddSketchState, UDDSKETCH_MERGE_NAME, UDDSKETCH_STATE_NAME};

src/common/function/src/aggr/uddsketch_state.rs

@@ -31,23 +31,28 @@ use datafusion::physical_plan::expressions::Literal;
 use datafusion::prelude::create_udaf;
 use datatypes::arrow::array::ArrayRef;
 use datatypes::arrow::datatypes::{DataType, Float64Type};
+use serde::{Deserialize, Serialize};
 use uddsketch::{SketchHashKey, UDDSketch};
 
 pub const UDDSKETCH_STATE_NAME: &str = "uddsketch_state";
 
-#[derive(Debug)]
+pub const UDDSKETCH_MERGE_NAME: &str = "uddsketch_merge";
+
+#[derive(Debug, Serialize, Deserialize)]
 pub struct UddSketchState {
     uddsketch: UDDSketch,
+    error_rate: f64,
 }
 
 impl UddSketchState {
     pub fn new(bucket_size: u64, error_rate: f64) -> Self {
         Self {
             uddsketch: UDDSketch::new(bucket_size, error_rate),
+            error_rate,
         }
     }
 
-    pub fn udf_impl() -> AggregateUDF {
+    pub fn state_udf_impl() -> AggregateUDF {
         create_udaf(
             UDDSKETCH_STATE_NAME,
             vec![DataType::Int64, DataType::Float64, DataType::Float64],
@@ -61,18 +66,55 @@ impl UddSketchState {
         )
     }
 
+    /// Create a UDF for the `uddsketch_merge` function.
+    ///
+    /// `uddsketch_merge` accepts bucket size, error rate, and a binary column of states generated by `uddsketch_state`
+    /// and merges them into a single state.
+    ///
+    /// The bucket size and error rate must be the same as the original state.
+    pub fn merge_udf_impl() -> AggregateUDF {
+        create_udaf(
+            UDDSKETCH_MERGE_NAME,
+            vec![DataType::Int64, DataType::Float64, DataType::Binary],
+            Arc::new(DataType::Binary),
+            Volatility::Immutable,
+            Arc::new(|args| {
+                let (bucket_size, error_rate) = downcast_accumulator_args(args)?;
+                Ok(Box::new(UddSketchState::new(bucket_size, error_rate)))
+            }),
+            Arc::new(vec![DataType::Binary]),
+        )
+    }
+
     fn update(&mut self, value: f64) {
         self.uddsketch.add_value(value);
     }
 
-    fn merge(&mut self, raw: &[u8]) {
-        if let Ok(uddsketch) = bincode::deserialize::<UDDSketch>(raw) {
-            if uddsketch.count() != 0 {
-                self.uddsketch.merge_sketch(&uddsketch);
+    fn merge(&mut self, raw: &[u8]) -> DfResult<()> {
+        if let Ok(uddsketch) = bincode::deserialize::<Self>(raw) {
+            if uddsketch.uddsketch.count() != 0 {
+                if self.uddsketch.max_allowed_buckets() != uddsketch.uddsketch.max_allowed_buckets()
+                    || (self.error_rate - uddsketch.error_rate).abs() >= 1e-9
+                {
+                    return Err(DataFusionError::Plan(format!(
+                        "Merging UDDSketch with different parameters: arguments={:?} vs actual input={:?}",
+                        (
+                            self.uddsketch.max_allowed_buckets(),
+                            self.error_rate
+                        ),
+                        (uddsketch.uddsketch.max_allowed_buckets(), uddsketch.error_rate)
+                    )));
+                }
+                self.uddsketch.merge_sketch(&uddsketch.uddsketch);
             }
         } else {
             trace!("Warning: Failed to deserialize UDDSketch from {:?}", raw);
+            return Err(DataFusionError::Plan(
+                "Failed to deserialize UDDSketch from binary".to_string(),
+            ));
         }
+
+        Ok(())
     }
 }
 
@@ -113,9 +155,21 @@ fn downcast_accumulator_args(args: AccumulatorArgs) -> DfResult<(u64, f64)> {
 impl DfAccumulator for UddSketchState {
     fn update_batch(&mut self, values: &[ArrayRef]) -> DfResult<()> {
         let array = &values[2]; // the third column is data value
-        let f64_array = as_primitive_array::<Float64Type>(array)?;
-        for v in f64_array.iter().flatten() {
-            self.update(v);
+        match array.data_type() {
+            DataType::Float64 => {
+                let f64_array = as_primitive_array::<Float64Type>(array)?;
+                for v in f64_array.iter().flatten() {
+                    self.update(v);
+                }
+            }
+            // meaning instantiate as `uddsketch_merge`
+            DataType::Binary => self.merge_batch(&[array.clone()])?,
+            _ => {
+                return not_impl_err!(
+                    "UDDSketch functions do not support data type: {}",
+                    array.data_type()
+                )
+            }
         }
 
         Ok(())
@@ -123,7 +177,7 @@ impl DfAccumulator for UddSketchState {
 
     fn evaluate(&mut self) -> DfResult<ScalarValue> {
         Ok(ScalarValue::Binary(Some(
-            bincode::serialize(&self.uddsketch).map_err(|e| {
+            bincode::serialize(&self).map_err(|e| {
                 DataFusionError::Internal(format!("Failed to serialize UDDSketch: {}", e))
             })?,
         )))
@@ -150,7 +204,7 @@ impl DfAccumulator for UddSketchState {
 
     fn state(&mut self) -> DfResult<Vec<ScalarValue>> {
         Ok(vec![ScalarValue::Binary(Some(
-            bincode::serialize(&self.uddsketch).map_err(|e| {
+            bincode::serialize(&self).map_err(|e| {
                 DataFusionError::Internal(format!("Failed to serialize UDDSketch: {}", e))
             })?,
         ))])
@@ -160,7 +214,7 @@ impl DfAccumulator for UddSketchState {
         let array = &states[0];
         let binary_array = as_binary_array(array)?;
         for v in binary_array.iter().flatten() {
-            self.merge(v);
+            self.merge(v)?;
         }
 
         Ok(())
@@ -182,8 +236,8 @@ mod tests {
 
         let result = state.evaluate().unwrap();
         if let ScalarValue::Binary(Some(bytes)) = result {
-            let deserialized: UDDSketch = bincode::deserialize(&bytes).unwrap();
-            assert_eq!(deserialized.count(), 3);
+            let deserialized: UddSketchState = bincode::deserialize(&bytes).unwrap();
+            assert_eq!(deserialized.uddsketch.count(), 3);
         } else {
             panic!("Expected binary scalar value");
         }
@@ -201,13 +255,15 @@ mod tests {
         // Create new state and merge the serialized data
         let mut new_state = UddSketchState::new(10, 0.01);
         if let ScalarValue::Binary(Some(bytes)) = &serialized {
-            new_state.merge(bytes);
+            new_state.merge(bytes).unwrap();
 
             // Verify the merged state matches original by comparing deserialized values
-            let original_sketch: UDDSketch = bincode::deserialize(bytes).unwrap();
+            let original_sketch: UddSketchState = bincode::deserialize(bytes).unwrap();
+            let original_sketch = original_sketch.uddsketch;
             let new_result = new_state.evaluate().unwrap();
             if let ScalarValue::Binary(Some(new_bytes)) = new_result {
-                let new_sketch: UDDSketch = bincode::deserialize(&new_bytes).unwrap();
+                let new_sketch: UddSketchState = bincode::deserialize(&new_bytes).unwrap();
+                let new_sketch = new_sketch.uddsketch;
                 assert_eq!(original_sketch.count(), new_sketch.count());
                 assert_eq!(original_sketch.sum(), new_sketch.sum());
                 assert_eq!(original_sketch.mean(), new_sketch.mean());
@@ -244,7 +300,8 @@ mod tests {
 
         let result = state.evaluate().unwrap();
         if let ScalarValue::Binary(Some(bytes)) = result {
-            let deserialized: UDDSketch = bincode::deserialize(&bytes).unwrap();
+            let deserialized: UddSketchState = bincode::deserialize(&bytes).unwrap();
+            let deserialized = deserialized.uddsketch;
             assert_eq!(deserialized.count(), 3);
         } else {
             panic!("Expected binary scalar value");
@@ -273,7 +330,8 @@ mod tests {
 
             let result = merged_state.evaluate().unwrap();
             if let ScalarValue::Binary(Some(bytes)) = result {
-                let deserialized: UDDSketch = bincode::deserialize(&bytes).unwrap();
+                let deserialized: UddSketchState = bincode::deserialize(&bytes).unwrap();
+                let deserialized = deserialized.uddsketch;
                 assert_eq!(deserialized.count(), 2);
             } else {
                 panic!("Expected binary scalar value");

src/common/function/src/scalars/timestamp.rs

@@ -13,10 +13,8 @@
 // limitations under the License.
 
 use std::sync::Arc;
-mod greatest;
 mod to_unixtime;
 
-use greatest::GreatestFunction;
 use to_unixtime::ToUnixtimeFunction;
 
 use crate::function_registry::FunctionRegistry;
@@ -26,6 +24,5 @@ pub(crate) struct TimestampFunction;
 impl TimestampFunction {
     pub fn register(registry: &FunctionRegistry) {
         registry.register(Arc::new(ToUnixtimeFunction));
-        registry.register(Arc::new(GreatestFunction));
     }
 }

src/common/function/src/scalars/timestamp/greatest.rs

@@ -1,328 +0,0 @@
-// Copyright 2023 Greptime Team
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-use std::fmt::{self};
-
-use common_query::error::{
-    self, ArrowComputeSnafu, InvalidFuncArgsSnafu, Result, UnsupportedInputDataTypeSnafu,
-};
-use common_query::prelude::{Signature, Volatility};
-use datafusion::arrow::compute::kernels::cmp::gt;
-use datatypes::arrow::array::AsArray;
-use datatypes::arrow::compute::cast;
-use datatypes::arrow::compute::kernels::zip;
-use datatypes::arrow::datatypes::{
-    DataType as ArrowDataType, Date32Type, TimeUnit, TimestampMicrosecondType,
-    TimestampMillisecondType, TimestampNanosecondType, TimestampSecondType,
-};
-use datatypes::prelude::ConcreteDataType;
-use datatypes::types::TimestampType;
-use datatypes::vectors::{Helper, VectorRef};
-use snafu::{ensure, ResultExt};
-
-use crate::function::{Function, FunctionContext};
-
-#[derive(Clone, Debug, Default)]
-pub struct GreatestFunction;
-
-const NAME: &str = "greatest";
-
-macro_rules! gt_time_types {
-    ($ty: ident, $columns:expr) => {{
-        let column1 = $columns[0].to_arrow_array();
-        let column2 = $columns[1].to_arrow_array();
-
-        let column1 = column1.as_primitive::<$ty>();
-        let column2 = column2.as_primitive::<$ty>();
-        let boolean_array = gt(&column1, &column2).context(ArrowComputeSnafu)?;
-
-        let result = zip::zip(&boolean_array, &column1, &column2).context(ArrowComputeSnafu)?;
-        Helper::try_into_vector(&result).context(error::FromArrowArraySnafu)
-    }};
-}
-
-impl Function for GreatestFunction {
-    fn name(&self) -> &str {
-        NAME
-    }
-
-    fn return_type(&self, input_types: &[ConcreteDataType]) -> Result<ConcreteDataType> {
-        ensure!(
-            input_types.len() == 2,
-            InvalidFuncArgsSnafu {
-                err_msg: format!(
-                    "The length of the args is not correct, expect exactly two, have: {}",
-                    input_types.len()
-                )
-            }
-        );
-
-        match &input_types[0] {
-            ConcreteDataType::String(_) => Ok(ConcreteDataType::timestamp_millisecond_datatype()),
-            ConcreteDataType::Date(_) => Ok(ConcreteDataType::date_datatype()),
-            ConcreteDataType::Timestamp(ts_type) => Ok(ConcreteDataType::Timestamp(*ts_type)),
-            _ => UnsupportedInputDataTypeSnafu {
-                function: NAME,
-                datatypes: input_types,
-            }
-            .fail(),
-        }
-    }
-
-    fn signature(&self) -> Signature {
-        Signature::uniform(
-            2,
-            vec![
-                ConcreteDataType::string_datatype(),
-                ConcreteDataType::date_datatype(),
-                ConcreteDataType::timestamp_nanosecond_datatype(),
-                ConcreteDataType::timestamp_microsecond_datatype(),
-                ConcreteDataType::timestamp_millisecond_datatype(),
-                ConcreteDataType::timestamp_second_datatype(),
-            ],
-            Volatility::Immutable,
-        )
-    }
-
-    fn eval(&self, _func_ctx: &FunctionContext, columns: &[VectorRef]) -> Result<VectorRef> {
-        ensure!(
-            columns.len() == 2,
-            InvalidFuncArgsSnafu {
-                err_msg: format!(
-                    "The length of the args is not correct, expect exactly two, have: {}",
-                    columns.len()
-                ),
-            }
-        );
-        match columns[0].data_type() {
-            ConcreteDataType::String(_) => {
-                let column1 = cast(
-                    &columns[0].to_arrow_array(),
-                    &ArrowDataType::Timestamp(TimeUnit::Millisecond, None),
-                )
-                .context(ArrowComputeSnafu)?;
-                let column1 = column1.as_primitive::<TimestampMillisecondType>();
-                let column2 = cast(
-                    &columns[1].to_arrow_array(),
-                    &ArrowDataType::Timestamp(TimeUnit::Millisecond, None),
-                )
-                .context(ArrowComputeSnafu)?;
-                let column2 = column2.as_primitive::<TimestampMillisecondType>();
-                let boolean_array = gt(&column1, &column2).context(ArrowComputeSnafu)?;
-                let result =
-                    zip::zip(&boolean_array, &column1, &column2).context(ArrowComputeSnafu)?;
-                Ok(Helper::try_into_vector(&result).context(error::FromArrowArraySnafu)?)
-            }
-            ConcreteDataType::Date(_) => gt_time_types!(Date32Type, columns),
-            ConcreteDataType::Timestamp(ts_type) => match ts_type {
-                TimestampType::Second(_) => gt_time_types!(TimestampSecondType, columns),
-                TimestampType::Millisecond(_) => {
-                    gt_time_types!(TimestampMillisecondType, columns)
-                }
-                TimestampType::Microsecond(_) => {
-                    gt_time_types!(TimestampMicrosecondType, columns)
-                }
-                TimestampType::Nanosecond(_) => {
-                    gt_time_types!(TimestampNanosecondType, columns)
-                }
-            },
-            _ => UnsupportedInputDataTypeSnafu {
-                function: NAME,
-                datatypes: columns.iter().map(|c| c.data_type()).collect::<Vec<_>>(),
-            }
-            .fail(),
-        }
-    }
-}
-
-impl fmt::Display for GreatestFunction {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "GREATEST")
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use std::sync::Arc;
-
-    use common_time::timestamp::TimeUnit;
-    use common_time::{Date, Timestamp};
-    use datatypes::types::{
-        DateType, TimestampMicrosecondType, TimestampMillisecondType, TimestampNanosecondType,
-        TimestampSecondType,
-    };
-    use datatypes::value::Value;
-    use datatypes::vectors::{
-        DateVector, StringVector, TimestampMicrosecondVector, TimestampMillisecondVector,
-        TimestampNanosecondVector, TimestampSecondVector, Vector,
-    };
-    use paste::paste;
-
-    use super::*;
-    #[test]
-    fn test_greatest_takes_string_vector() {
-        let function = GreatestFunction;
-        assert_eq!(
-            function
-                .return_type(&[
-                    ConcreteDataType::string_datatype(),
-                    ConcreteDataType::string_datatype()
-                ])
-                .unwrap(),
-            ConcreteDataType::timestamp_millisecond_datatype()
-        );
-        let columns = vec![
-            Arc::new(StringVector::from(vec![
-                "1970-01-01".to_string(),
-                "2012-12-23".to_string(),
-            ])) as _,
-            Arc::new(StringVector::from(vec![
-                "2001-02-01".to_string(),
-                "1999-01-01".to_string(),
-            ])) as _,
-        ];
-
-        let result = function
-            .eval(&FunctionContext::default(), &columns)
-            .unwrap();
-        let result = result
-            .as_any()
-            .downcast_ref::<TimestampMillisecondVector>()
-            .unwrap();
-        assert_eq!(result.len(), 2);
-        assert_eq!(
-            result.get(0),
-            Value::Timestamp(Timestamp::from_str("2001-02-01 00:00:00", None).unwrap())
-        );
-        assert_eq!(
-            result.get(1),
-            Value::Timestamp(Timestamp::from_str("2012-12-23 00:00:00", None).unwrap())
-        );
-    }
-
-    #[test]
-    fn test_greatest_takes_date_vector() {
-        let function = GreatestFunction;
-        assert_eq!(
-            function
-                .return_type(&[
-                    ConcreteDataType::date_datatype(),
-                    ConcreteDataType::date_datatype()
-                ])
-                .unwrap(),
-            ConcreteDataType::Date(DateType)
-        );
-
-        let columns = vec![
-            Arc::new(DateVector::from_slice(vec![-1, 2])) as _,
-            Arc::new(DateVector::from_slice(vec![0, 1])) as _,
-        ];
-
-        let result = function
-            .eval(&FunctionContext::default(), &columns)
-            .unwrap();
-        let result = result.as_any().downcast_ref::<DateVector>().unwrap();
-        assert_eq!(result.len(), 2);
-        assert_eq!(
-            result.get(0),
-            Value::Date(Date::from_str_utc("1970-01-01").unwrap())
-        );
-        assert_eq!(
-            result.get(1),
-            Value::Date(Date::from_str_utc("1970-01-03").unwrap())
-        );
-    }
-
-    #[test]
-    fn test_greatest_takes_datetime_vector() {
-        let function = GreatestFunction;
-        assert_eq!(
-            function
-                .return_type(&[
-                    ConcreteDataType::timestamp_millisecond_datatype(),
-                    ConcreteDataType::timestamp_millisecond_datatype()
-                ])
-                .unwrap(),
-            ConcreteDataType::timestamp_millisecond_datatype()
-        );
-
-        let columns = vec![
-            Arc::new(TimestampMillisecondVector::from_slice(vec![-1, 2])) as _,
-            Arc::new(TimestampMillisecondVector::from_slice(vec![0, 1])) as _,
-        ];
-
-        let result = function
-            .eval(&FunctionContext::default(), &columns)
-            .unwrap();
-        let result = result
-            .as_any()
-            .downcast_ref::<TimestampMillisecondVector>()
-            .unwrap();
-        assert_eq!(result.len(), 2);
-        assert_eq!(
-            result.get(0),
-            Value::Timestamp(Timestamp::from_str("1970-01-01 00:00:00", None).unwrap())
-        );
-        assert_eq!(
-            result.get(1),
-            Value::Timestamp(Timestamp::from_str("1970-01-01 00:00:00.002", None).unwrap())
-        );
-    }
-
-    macro_rules! test_timestamp {
-        ($type: expr,$unit: ident) => {
-            paste! {
-                #[test]
-                fn [<test_greatest_takes_ $unit:lower _vector>]() {
-                    let function = GreatestFunction;
-                    assert_eq!(
-                        function.return_type(&[$type, $type]).unwrap(),
-                        ConcreteDataType::Timestamp(TimestampType::$unit([<Timestamp $unit Type>]))
-                    );
-
-                    let columns = vec![
-                        Arc::new([<Timestamp $unit Vector>]::from_slice(vec![-1, 2])) as _,
-                        Arc::new([<Timestamp $unit Vector>]::from_slice(vec![0, 1])) as _,
-                    ];
-
-                    let result = function.eval(&FunctionContext::default(), &columns).unwrap();
-                    let result = result.as_any().downcast_ref::<[<Timestamp $unit Vector>]>().unwrap();
-                    assert_eq!(result.len(), 2);
-                    assert_eq!(
-                        result.get(0),
-                        Value::Timestamp(Timestamp::new(0, TimeUnit::$unit))
-                    );
-                    assert_eq!(
-                        result.get(1),
-                        Value::Timestamp(Timestamp::new(2, TimeUnit::$unit))
-                    );
-                }
-            }
-        }
-    }
-
-    test_timestamp!(
-        ConcreteDataType::timestamp_nanosecond_datatype(),
-        Nanosecond
-    );
-    test_timestamp!(
-        ConcreteDataType::timestamp_microsecond_datatype(),
-        Microsecond
-    );
-    test_timestamp!(
-        ConcreteDataType::timestamp_millisecond_datatype(),
-        Millisecond
-    );
-    test_timestamp!(ConcreteDataType::timestamp_second_datatype(), Second);
-}

src/common/meta/src/instruction.rs

@@ -217,7 +217,9 @@ pub enum Instruction {
     /// Invalidates batch cache.
     InvalidateCaches(Vec<CacheIdent>),
     /// Flushes regions.
-    FlushRegion(FlushRegions),
+    FlushRegions(FlushRegions),
+    /// Flushes a single region.
+    FlushRegion(RegionId),
 }
 
 /// The reply of [UpgradeRegion].
@@ -248,6 +250,7 @@ pub enum InstructionReply {
     CloseRegion(SimpleReply),
     UpgradeRegion(UpgradeRegionReply),
     DowngradeRegion(DowngradeRegionReply),
+    FlushRegion(SimpleReply),
 }
 
 impl Display for InstructionReply {
@@ -259,6 +262,7 @@ impl Display for InstructionReply {
             Self::DowngradeRegion(reply) => {
                 write!(f, "InstructionReply::DowngradeRegion({})", reply)
             }
+            Self::FlushRegion(reply) => write!(f, "InstructionReply::FlushRegion({})", reply),
         }
     }
 }

src/common/meta/src/key.rs

@@ -112,7 +112,7 @@ pub mod test_utils;
 mod tombstone;
 pub mod topic_name;
 pub mod topic_region;
-pub(crate) mod txn_helper;
+pub mod txn_helper;
 pub mod view_info;
 
 use std::collections::{BTreeMap, HashMap, HashSet};

src/common/meta/src/key/txn_helper.rs

@@ -25,7 +25,7 @@ pub struct TxnOpGetResponseSet(Vec<KeyValue>);
 
 impl TxnOpGetResponseSet {
     /// Returns a filter to consume a [KeyValue] where the key equals `key`.
-    pub(crate) fn filter(key: Vec<u8>) -> impl FnMut(&mut TxnOpGetResponseSet) -> Option<Vec<u8>> {
+    pub fn filter(key: Vec<u8>) -> impl FnMut(&mut TxnOpGetResponseSet) -> Option<Vec<u8>> {
         move |set| {
             let pos = set.0.iter().position(|kv| kv.key == key);
             match pos {
@@ -36,7 +36,7 @@ impl TxnOpGetResponseSet {
     }
 
     /// Returns a decoder to decode bytes to `DeserializedValueWithBytes<T>`.
-    pub(crate) fn decode_with<F, T>(
+    pub fn decode_with<F, T>(
         mut f: F,
     ) -> impl FnMut(&mut TxnOpGetResponseSet) -> Result<Option<DeserializedValueWithBytes<T>>>
     where

src/common/meta/src/kv_backend.rs

@@ -35,7 +35,7 @@ pub mod memory;
 pub mod rds;
 pub mod test;
 pub mod txn;
-
+pub mod util;
 pub type KvBackendRef<E = Error> = Arc<dyn KvBackend<Error = E> + Send + Sync>;
 
 #[async_trait]

src/common/meta/src/kv_backend/util.rs

@@ -0,0 +1,85 @@
+// Copyright 2023 Greptime Team
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/// Removes sensitive information like passwords from connection strings.
+///
+/// This function sanitizes connection strings by removing credentials:
+/// - For URL format (mysql://user:password@host:port/db): Removes everything before '@'
+/// - For parameter format (host=localhost password=secret): Removes the password parameter
+/// - For URL format without credentials (mysql://host:port/db): Removes the protocol prefix
+///
+/// # Arguments
+///
+/// * `conn_str` - The connection string to sanitize
+///
+/// # Returns
+///
+/// A sanitized version of the connection string with sensitive information removed
+pub fn sanitize_connection_string(conn_str: &str) -> String {
+    // Case 1: URL format with credentials (mysql://user:password@host:port/db)
+    // Extract everything after the '@' symbol
+    if let Some(at_pos) = conn_str.find('@') {
+        return conn_str[at_pos + 1..].to_string();
+    }
+
+    // Case 2: Parameter format with password (host=localhost password=secret dbname=mydb)
+    // Filter out any parameter that starts with "password="
+    if conn_str.contains("password=") {
+        return conn_str
+            .split_whitespace()
+            .filter(|param| !param.starts_with("password="))
+            .collect::<Vec<_>>()
+            .join(" ");
+    }
+
+    // Case 3: URL format without credentials (mysql://host:port/db)
+    // Extract everything after the protocol prefix
+    if let Some(host_part) = conn_str.split("://").nth(1) {
+        return host_part.to_string();
+    }
+
+    // Case 4: Already sanitized or unknown format
+    // Return as is
+    conn_str.to_string()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_sanitize_connection_string() {
+        // Test URL format with username/password
+        let conn_str = "mysql://user:password123@localhost:3306/db";
+        assert_eq!(sanitize_connection_string(conn_str), "localhost:3306/db");
+
+        // Test URL format without credentials
+        let conn_str = "mysql://localhost:3306/db";
+        assert_eq!(sanitize_connection_string(conn_str), "localhost:3306/db");
+
+        // Test parameter format with password
+        let conn_str = "host=localhost port=5432 user=postgres password=secret dbname=mydb";
+        assert_eq!(
+            sanitize_connection_string(conn_str),
+            "host=localhost port=5432 user=postgres dbname=mydb"
+        );
+
+        // Test parameter format without password
+        let conn_str = "host=localhost port=5432 user=postgres dbname=mydb";
+        assert_eq!(
+            sanitize_connection_string(conn_str),
+            "host=localhost port=5432 user=postgres dbname=mydb"
+        );
+    }
+}

src/datanode/src/heartbeat/handler.rs

@@ -39,6 +39,7 @@ pub struct RegionHeartbeatResponseHandler {
     region_server: RegionServer,
     catchup_tasks: TaskTracker<()>,
     downgrade_tasks: TaskTracker<()>,
+    flush_tasks: TaskTracker<()>,
 }
 
 /// Handler of the instruction.
@@ -50,6 +51,7 @@ pub struct HandlerContext {
     region_server: RegionServer,
     catchup_tasks: TaskTracker<()>,
     downgrade_tasks: TaskTracker<()>,
+    flush_tasks: TaskTracker<()>,
 }
 
 impl HandlerContext {
@@ -63,6 +65,7 @@ impl HandlerContext {
             region_server,
             catchup_tasks: TaskTracker::new(),
             downgrade_tasks: TaskTracker::new(),
+            flush_tasks: TaskTracker::new(),
         }
     }
 }
@@ -74,6 +77,7 @@ impl RegionHeartbeatResponseHandler {
             region_server,
             catchup_tasks: TaskTracker::new(),
             downgrade_tasks: TaskTracker::new(),
+            flush_tasks: TaskTracker::new(),
         }
     }
 
@@ -95,8 +99,11 @@ impl RegionHeartbeatResponseHandler {
                 handler_context.handle_upgrade_region_instruction(upgrade_region)
             })),
             Instruction::InvalidateCaches(_) => InvalidHeartbeatResponseSnafu.fail(),
-            Instruction::FlushRegion(flush_regions) => Ok(Box::new(move |handler_context| {
-                handler_context.handle_flush_region_instruction(flush_regions)
+            Instruction::FlushRegions(flush_regions) => Ok(Box::new(move |handler_context| {
+                handler_context.handle_flush_regions_instruction(flush_regions)
+            })),
+            Instruction::FlushRegion(flush_region) => Ok(Box::new(move |handler_context| {
+                handler_context.handle_flush_region_instruction(flush_region)
             })),
         }
     }
@@ -111,6 +118,7 @@ impl HeartbeatResponseHandler for RegionHeartbeatResponseHandler {
                 | Some((_, Instruction::CloseRegion { .. }))
                 | Some((_, Instruction::DowngradeRegion { .. }))
                 | Some((_, Instruction::UpgradeRegion { .. }))
+                | Some((_, Instruction::FlushRegion { .. }))
         )
     }
 
@@ -124,12 +132,14 @@ impl HeartbeatResponseHandler for RegionHeartbeatResponseHandler {
         let region_server = self.region_server.clone();
         let catchup_tasks = self.catchup_tasks.clone();
         let downgrade_tasks = self.downgrade_tasks.clone();
+        let flush_tasks = self.flush_tasks.clone();
         let handler = Self::build_handler(instruction)?;
         let _handle = common_runtime::spawn_global(async move {
             let reply = handler(HandlerContext {
                 region_server,
                 catchup_tasks,
                 downgrade_tasks,
+                flush_tasks,
             })
             .await;
 

src/datanode/src/heartbeat/handler/flush_region.rs

@@ -12,16 +12,17 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-use common_meta::instruction::{FlushRegions, InstructionReply};
+use common_meta::instruction::{FlushRegions, InstructionReply, SimpleReply};
 use common_telemetry::warn;
 use futures_util::future::BoxFuture;
 use store_api::region_request::{RegionFlushRequest, RegionRequest};
+use store_api::storage::RegionId;
 
 use crate::error;
 use crate::heartbeat::handler::HandlerContext;
 
 impl HandlerContext {
-    pub(crate) fn handle_flush_region_instruction(
+    pub(crate) fn handle_flush_regions_instruction(
         self,
         flush_regions: FlushRegions,
     ) -> BoxFuture<'static, Option<InstructionReply>> {
@@ -49,6 +50,59 @@ impl HandlerContext {
             None
         })
     }
+
+    pub(crate) fn handle_flush_region_instruction(
+        self,
+        region_id: RegionId,
+    ) -> BoxFuture<'static, Option<InstructionReply>> {
+        Box::pin(async move {
+            let Some(writable) = self.region_server.is_region_leader(region_id) else {
+                return Some(InstructionReply::FlushRegion(SimpleReply {
+                    result: false,
+                    error: Some("Region is not leader".to_string()),
+                }));
+            };
+
+            if !writable {
+                return Some(InstructionReply::FlushRegion(SimpleReply {
+                    result: false,
+                    error: Some("Region is not writable".to_string()),
+                }));
+            }
+
+            let region_server_moved = self.region_server.clone();
+            let register_result = self
+                .flush_tasks
+                .try_register(
+                    region_id,
+                    Box::pin(async move {
+                        let request = RegionRequest::Flush(RegionFlushRequest {
+                            row_group_size: None,
+                        });
+                        region_server_moved
+                            .handle_request(region_id, request)
+                            .await?;
+                        Ok(())
+                    }),
+                )
+                .await;
+            if register_result.is_busy() {
+                warn!("Another flush task is running for the region: {region_id}");
+            }
+            let mut watcher = register_result.into_watcher();
+            let result = self.flush_tasks.wait_until_finish(&mut watcher).await;
+            match result {
+                Ok(()) => Some(InstructionReply::FlushRegion(SimpleReply {
+                    result: true,
+                    error: None,
+                })),
+                Err(err) => Some(InstructionReply::FlushRegion(SimpleReply {
+                    result: false,
+                    error: Some(format!("{err:?}")),
+                })),
+            }
+        })
+    }
 }
 
 #[cfg(test)]
@@ -84,7 +138,7 @@ mod tests {
 
         let reply = handler_context
             .clone()
-            .handle_flush_region_instruction(FlushRegions {
+            .handle_flush_regions_instruction(FlushRegions {
                 region_ids: region_ids.clone(),
             })
             .await;
@@ -94,7 +148,7 @@ mod tests {
         flushed_region_ids.write().unwrap().clear();
         let not_found_region_ids = (0..2).map(|i| RegionId::new(2048, i)).collect::<Vec<_>>();
         let reply = handler_context
-            .handle_flush_region_instruction(FlushRegions {
+            .handle_flush_regions_instruction(FlushRegions {
                 region_ids: not_found_region_ids.clone(),
             })
             .await;

src/datanode/src/heartbeat/task_tracker.rs

@@ -144,6 +144,11 @@ impl<T: Send + Sync + Clone + 'static> TaskTracker<T> {
         }
     }
 
+    /// Waits for a [RegisterResult] and returns a [WaitResult].
+    pub(crate) async fn wait_until_finish(&self, watcher: &mut TaskWatcher<T>) -> Result<T> {
+        wait(watcher).await
+    }
+
     /// Tries to register a new async task, returns [RegisterResult::Busy] if previous task is running.
     pub(crate) async fn try_register(
         &self,

src/flow/src/adapter/flownode_impl.rs

@@ -37,11 +37,12 @@ use tokio::sync::{Mutex, RwLock};
 
 use crate::adapter::{CreateFlowArgs, StreamingEngine};
 use crate::batching_mode::engine::BatchingEngine;
+use crate::batching_mode::{FRONTEND_SCAN_TIMEOUT, MIN_REFRESH_DURATION};
 use crate::engine::FlowEngine;
 use crate::error::{
     CreateFlowSnafu, ExternalSnafu, FlowNotFoundSnafu, IllegalCheckTaskStateSnafu,
-    InsertIntoFlowSnafu, InternalSnafu, JoinTaskSnafu, ListFlowsSnafu, SyncCheckTaskSnafu,
-    UnexpectedSnafu,
+    InsertIntoFlowSnafu, InternalSnafu, JoinTaskSnafu, ListFlowsSnafu, NoAvailableFrontendSnafu,
+    SyncCheckTaskSnafu, UnexpectedSnafu,
 };
 use crate::metrics::METRIC_FLOW_TASK_COUNT;
 use crate::repr::{self, DiffRow};
@@ -81,6 +82,11 @@ impl FlowDualEngine {
         }
     }
 
+    /// Determine if the engine is in distributed mode
+    pub fn is_distributed(&self) -> bool {
+        self.streaming_engine.node_id.is_some()
+    }
+
     pub fn streaming_engine(&self) -> Arc<StreamingEngine> {
         self.streaming_engine.clone()
     }
@@ -89,6 +95,39 @@ impl FlowDualEngine {
         self.batching_engine.clone()
     }
 
+    /// In distributed mode, scan periodically(1s) until available frontend is found, or timeout,
+    /// in standalone mode, return immediately
+    /// notice here if any frontend appear in cluster info this function will return immediately
+    async fn wait_for_available_frontend(&self, timeout: std::time::Duration) -> Result<(), Error> {
+        if !self.is_distributed() {
+            return Ok(());
+        }
+        let frontend_client = self.batching_engine().frontend_client.clone();
+        let sleep_duration = std::time::Duration::from_millis(1_000);
+        let now = std::time::Instant::now();
+        loop {
+            let frontend_list = frontend_client.scan_for_frontend().await?;
+            if !frontend_list.is_empty() {
+                let fe_list = frontend_list
+                    .iter()
+                    .map(|(_, info)| &info.peer.addr)
+                    .collect::<Vec<_>>();
+                info!("Available frontend found: {:?}", fe_list);
+                return Ok(());
+            }
+            let elapsed = now.elapsed();
+            tokio::time::sleep(sleep_duration).await;
+            info!("Waiting for available frontend, elapsed={:?}", elapsed);
+            if elapsed >= timeout {
+                return NoAvailableFrontendSnafu {
+                    timeout,
+                    context: "No available frontend found in cluster info",
+                }
+                .fail();
+            }
+        }
+    }
+
     /// Try to sync with check task, this is only used in drop flow&flush flow, so a flow id is required
     ///
     /// the need to sync is to make sure flush flow actually get called
@@ -338,18 +377,36 @@ struct ConsistentCheckTask {
 
 impl ConsistentCheckTask {
     async fn start_check_task(engine: &Arc<FlowDualEngine>) -> Result<Self, Error> {
-        // first do recover flows
-        engine.check_flow_consistent(true, false).await?;
-
-        let inner = engine.clone();
+        let engine = engine.clone();
         let (tx, mut rx) = tokio::sync::mpsc::channel(1);
         let (trigger_tx, mut trigger_rx) =
             tokio::sync::mpsc::channel::<(bool, bool, tokio::sync::oneshot::Sender<()>)>(10);
         let handle = common_runtime::spawn_global(async move {
+            // first check if available frontend is found
+            if let Err(err) = engine
+                .wait_for_available_frontend(FRONTEND_SCAN_TIMEOUT)
+                .await
+            {
+                warn!("No frontend is available yet:\n {err:?}");
+            }
+
+            // then do recover flows, if failed, always retry
+            let mut recover_retry = 0;
+            while let Err(err) = engine.check_flow_consistent(true, false).await {
+                recover_retry += 1;
+                error!(
+                    "Failed to recover flows:\n {err:?}, retry {} in {}s",
+                    recover_retry,
+                    MIN_REFRESH_DURATION.as_secs()
+                );
+                tokio::time::sleep(MIN_REFRESH_DURATION).await;
+            }
+
+            // then do check flows, with configurable allow_create and allow_drop
             let (mut allow_create, mut allow_drop) = (false, false);
             let mut ret_signal: Option<tokio::sync::oneshot::Sender<()>> = None;
             loop {
-                if let Err(err) = inner.check_flow_consistent(allow_create, allow_drop).await {
+                if let Err(err) = engine.check_flow_consistent(allow_create, allow_drop).await {
                     error!(err; "Failed to check flow consistent");
                 }
                 if let Some(done) = ret_signal.take() {
@@ -534,7 +591,12 @@ impl FlowEngine for FlowDualEngine {
         match flow_type {
             Some(FlowType::Batching) => self.batching_engine.flush_flow(flow_id).await,
             Some(FlowType::Streaming) => self.streaming_engine.flush_flow(flow_id).await,
-            None => Ok(0),
+            None => {
+                warn!(
+                    "Currently flow={flow_id} doesn't exist in flownode, ignore flush_flow request"
+                );
+                Ok(0)
+            }
         }
     }
 

src/flow/src/batching_mode.rs

@@ -31,10 +31,19 @@ pub const DEFAULT_BATCHING_ENGINE_QUERY_TIMEOUT: Duration = Duration::from_secs(
 pub const SLOW_QUERY_THRESHOLD: Duration = Duration::from_secs(60);
 
 /// The minimum duration between two queries execution by batching mode task
-const MIN_REFRESH_DURATION: Duration = Duration::new(5, 0);
+pub const MIN_REFRESH_DURATION: Duration = Duration::new(5, 0);
 
 /// Grpc connection timeout
 const GRPC_CONN_TIMEOUT: Duration = Duration::from_secs(5);
 
 /// Grpc max retry number
 const GRPC_MAX_RETRIES: u32 = 3;
+
+/// Flow wait for available frontend timeout,
+/// if failed to find available frontend after FRONTEND_SCAN_TIMEOUT elapsed, return error
+/// which should prevent flownode from starting
+pub const FRONTEND_SCAN_TIMEOUT: Duration = Duration::from_secs(30);
+
+/// Frontend activity timeout
+/// if frontend is down(not sending heartbeat) for more than FRONTEND_ACTIVITY_TIMEOUT, it will be removed from the list that flownode use to connect
+pub const FRONTEND_ACTIVITY_TIMEOUT: Duration = Duration::from_secs(60);

src/flow/src/batching_mode/engine.rs

@@ -49,7 +49,8 @@ use crate::{CreateFlowArgs, Error, FlowId, TableName};
 pub struct BatchingEngine {
     tasks: RwLock<BTreeMap<FlowId, BatchingTask>>,
     shutdown_txs: RwLock<BTreeMap<FlowId, oneshot::Sender<()>>>,
-    frontend_client: Arc<FrontendClient>,
+    /// frontend client for insert request
+    pub(crate) frontend_client: Arc<FrontendClient>,
     flow_metadata_manager: FlowMetadataManagerRef,
     table_meta: TableMetadataManagerRef,
     catalog_manager: CatalogManagerRef,

src/flow/src/batching_mode/frontend_client.rs

@@ -15,6 +15,7 @@
 //! Frontend client to run flow as batching task which is time-window-aware normal query triggered every tick set by user
 
 use std::sync::{Arc, Weak};
+use std::time::SystemTime;
 
 use api::v1::greptime_request::Request;
 use api::v1::CreateTableExpr;
@@ -26,15 +27,17 @@ use common_meta::peer::Peer;
 use common_meta::rpc::store::RangeRequest;
 use common_query::Output;
 use common_telemetry::warn;
+use itertools::Itertools;
 use meta_client::client::MetaClient;
 use servers::query_handler::grpc::GrpcQueryHandler;
 use session::context::{QueryContextBuilder, QueryContextRef};
 use snafu::{OptionExt, ResultExt};
 
 use crate::batching_mode::{
-    DEFAULT_BATCHING_ENGINE_QUERY_TIMEOUT, GRPC_CONN_TIMEOUT, GRPC_MAX_RETRIES,
+    DEFAULT_BATCHING_ENGINE_QUERY_TIMEOUT, FRONTEND_ACTIVITY_TIMEOUT, GRPC_CONN_TIMEOUT,
+    GRPC_MAX_RETRIES,
 };
-use crate::error::{ExternalSnafu, InvalidRequestSnafu, UnexpectedSnafu};
+use crate::error::{ExternalSnafu, InvalidRequestSnafu, NoAvailableFrontendSnafu, UnexpectedSnafu};
 use crate::Error;
 
 /// Just like [`GrpcQueryHandler`] but use BoxedError
@@ -127,10 +130,24 @@ impl DatabaseWithPeer {
     fn new(database: Database, peer: Peer) -> Self {
         Self { database, peer }
     }
+
+    /// Try sending a "SELECT 1" to the database
+    async fn try_select_one(&self) -> Result<(), Error> {
+        // notice here use `sql` for `SELECT 1` return 1 row
+        let _ = self
+            .database
+            .sql("SELECT 1")
+            .await
+            .with_context(|_| InvalidRequestSnafu {
+                context: format!("Failed to handle `SELECT 1` request at {:?}", self.peer),
+            })?;
+        Ok(())
+    }
 }
 
 impl FrontendClient {
-    async fn scan_for_frontend(&self) -> Result<Vec<(NodeInfoKey, NodeInfo)>, Error> {
+    /// scan for available frontend from metadata
+    pub(crate) async fn scan_for_frontend(&self) -> Result<Vec<(NodeInfoKey, NodeInfo)>, Error> {
         let Self::Distributed { meta_client, .. } = self else {
             return Ok(vec![]);
         };
@@ -160,8 +177,8 @@ impl FrontendClient {
         Ok(res)
     }
 
-    /// Get the database with max `last_activity_ts`
-    async fn get_last_active_frontend(
+    /// Get the database with maximum `last_activity_ts`& is able to process query
+    async fn get_latest_active_frontend(
         &self,
         catalog: &str,
         schema: &str,
@@ -177,22 +194,50 @@ impl FrontendClient {
             .fail();
         };
 
-        let frontends = self.scan_for_frontend().await?;
-        let mut peer = None;
+        let mut interval = tokio::time::interval(GRPC_CONN_TIMEOUT);
+        interval.tick().await;
+        for retry in 0..GRPC_MAX_RETRIES {
+            let frontends = self.scan_for_frontend().await?;
+            let now_in_ms = SystemTime::now()
+                .duration_since(SystemTime::UNIX_EPOCH)
+                .unwrap()
+                .as_millis() as i64;
 
-        if let Some((_, val)) = frontends.iter().max_by_key(|(_, val)| val.last_activity_ts) {
-            peer = Some(val.peer.clone());
+            // found node with maximum last_activity_ts
+            for (_, node_info) in frontends
+                .iter()
+                .sorted_by_key(|(_, node_info)| node_info.last_activity_ts)
+                .rev()
+                // filter out frontend that have been down for more than 1 min
+                .filter(|(_, node_info)| {
+                    node_info.last_activity_ts + FRONTEND_ACTIVITY_TIMEOUT.as_millis() as i64
+                        > now_in_ms
+                })
+            {
+                let addr = &node_info.peer.addr;
+                let client = Client::with_manager_and_urls(chnl_mgr.clone(), vec![addr.clone()]);
+                let database = Database::new(catalog, schema, client);
+                let db = DatabaseWithPeer::new(database, node_info.peer.clone());
+                match db.try_select_one().await {
+                    Ok(_) => return Ok(db),
+                    Err(e) => {
+                        warn!(
+                            "Failed to connect to frontend {} on retry={}: \n{e:?}",
+                            addr, retry
+                        );
+                    }
+                }
+            }
+            // no available frontend
+            // sleep and retry
+            interval.tick().await;
         }
 
-        let Some(peer) = peer else {
-            UnexpectedSnafu {
-                reason: format!("No frontend available: {:?}", frontends),
-            }
-            .fail()?
-        };
-        let client = Client::with_manager_and_urls(chnl_mgr.clone(), vec![peer.addr.clone()]);
-        let database = Database::new(catalog, schema, client);
-        Ok(DatabaseWithPeer::new(database, peer))
+        NoAvailableFrontendSnafu {
+            timeout: GRPC_CONN_TIMEOUT,
+            context: "No available frontend found that is able to process query",
+        }
+        .fail()
     }
 
     pub async fn create(
@@ -222,38 +267,18 @@ impl FrontendClient {
     ) -> Result<u32, Error> {
         match self {
             FrontendClient::Distributed { .. } => {
-                let db = self.get_last_active_frontend(catalog, schema).await?;
+                let db = self.get_latest_active_frontend(catalog, schema).await?;
 
                 *peer_desc = Some(PeerDesc::Dist {
                     peer: db.peer.clone(),
                 });
 
-                let mut retry = 0;
-
-                loop {
-                    let ret = db.database.handle(req.clone()).await.with_context(|_| {
-                        InvalidRequestSnafu {
-                            context: format!("Failed to handle request: {:?}", req),
-                        }
-                    });
-                    if let Err(err) = ret {
-                        if retry < GRPC_MAX_RETRIES {
-                            retry += 1;
-                            warn!(
-                                "Failed to send request to grpc handle at Peer={:?}, retry = {}, error = {:?}",
-                                db.peer, retry, err
-                            );
-                            continue;
-                        } else {
-                            common_telemetry::error!(
-                                "Failed to send request to grpc handle at Peer={:?} after {} retries, error = {:?}",
-                                db.peer, retry, err
-                            );
-                            return Err(err);
-                        }
-                    }
-                    return ret;
-                }
+                db.database
+                    .handle_with_retry(req.clone(), GRPC_MAX_RETRIES)
+                    .await
+                    .with_context(|_| InvalidRequestSnafu {
+                        context: format!("Failed to handle request at {:?}: {:?}", db.peer, req),
+                    })
             }
             FrontendClient::Standalone { database_client } => {
                 let ctx = QueryContextBuilder::default()

src/flow/src/error.rs

@@ -61,6 +61,16 @@ pub enum Error {
         location: Location,
     },
 
+    #[snafu(display(
+        "No available frontend found after timeout: {timeout:?}, context: {context}"
+    ))]
+    NoAvailableFrontend {
+        timeout: std::time::Duration,
+        context: String,
+        #[snafu(implicit)]
+        location: Location,
+    },
+
     #[snafu(display("External error"))]
     External {
         source: BoxedError,
@@ -296,7 +306,8 @@ impl ErrorExt for Error {
             Self::Eval { .. }
             | Self::JoinTask { .. }
             | Self::Datafusion { .. }
-            | Self::InsertIntoFlow { .. } => StatusCode::Internal,
+            | Self::InsertIntoFlow { .. }
+            | Self::NoAvailableFrontend { .. } => StatusCode::Internal,
             Self::FlowAlreadyExist { .. } => StatusCode::TableAlreadyExists,
             Self::TableNotFound { .. }
             | Self::TableNotFoundMeta { .. }

src/flow/src/server.rs

@@ -172,6 +172,8 @@ impl FlownodeServer {
     }
 
     /// Start the background task for streaming computation.
+    ///
+    /// Should be called only after heartbeat is establish, hence can get cluster info
     async fn start_workers(&self) -> Result<(), Error> {
         let manager_ref = self.inner.flow_service.dual_engine.clone();
         let handle = manager_ref

src/meta-srv/src/metasrv.rs

@@ -14,7 +14,7 @@
 
 pub mod builder;
 
-use std::fmt::Display;
+use std::fmt::{self, Display};
 use std::sync::atomic::{AtomicBool, Ordering};
 use std::sync::{Arc, Mutex, RwLock};
 use std::time::Duration;
@@ -48,6 +48,7 @@ use serde::{Deserialize, Serialize};
 use servers::export_metrics::ExportMetricsOption;
 use servers::http::HttpOptions;
 use snafu::{OptionExt, ResultExt};
+use store_api::storage::RegionId;
 use table::metadata::TableId;
 use tokio::sync::broadcast::error::RecvError;
 
@@ -65,7 +66,7 @@ use crate::procedure::wal_prune::manager::WalPruneTickerRef;
 use crate::procedure::ProcedureManagerListenerAdapter;
 use crate::pubsub::{PublisherRef, SubscriptionManagerRef};
 use crate::region::supervisor::RegionSupervisorTickerRef;
-use crate::selector::{Selector, SelectorType};
+use crate::selector::{RegionStatAwareSelector, Selector, SelectorType};
 use crate::service::mailbox::MailboxRef;
 use crate::service::store::cached_kv::LeaderCachedKvBackend;
 use crate::state::{become_follower, become_leader, StateRef};
@@ -96,7 +97,7 @@ pub enum BackendImpl {
     MysqlStore,
 }
 
-#[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
+#[derive(Clone, PartialEq, Serialize, Deserialize)]
 #[serde(default)]
 pub struct MetasrvOptions {
     /// The address the server listens on.
@@ -166,6 +167,47 @@ pub struct MetasrvOptions {
     pub node_max_idle_time: Duration,
 }
 
+impl fmt::Debug for MetasrvOptions {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let mut debug_struct = f.debug_struct("MetasrvOptions");
+        debug_struct
+            .field("bind_addr", &self.bind_addr)
+            .field("server_addr", &self.server_addr)
+            .field("store_addrs", &self.sanitize_store_addrs())
+            .field("selector", &self.selector)
+            .field("use_memory_store", &self.use_memory_store)
+            .field("enable_region_failover", &self.enable_region_failover)
+            .field(
+                "allow_region_failover_on_local_wal",
+                &self.allow_region_failover_on_local_wal,
+            )
+            .field("http", &self.http)
+            .field("logging", &self.logging)
+            .field("procedure", &self.procedure)
+            .field("failure_detector", &self.failure_detector)
+            .field("datanode", &self.datanode)
+            .field("enable_telemetry", &self.enable_telemetry)
+            .field("data_home", &self.data_home)
+            .field("wal", &self.wal)
+            .field("export_metrics", &self.export_metrics)
+            .field("store_key_prefix", &self.store_key_prefix)
+            .field("max_txn_ops", &self.max_txn_ops)
+            .field("flush_stats_factor", &self.flush_stats_factor)
+            .field("tracing", &self.tracing)
+            .field("backend", &self.backend);
+
+        #[cfg(any(feature = "pg_kvbackend", feature = "mysql_kvbackend"))]
+        debug_struct.field("meta_table_name", &self.meta_table_name);
+
+        #[cfg(feature = "pg_kvbackend")]
+        debug_struct.field("meta_election_lock_id", &self.meta_election_lock_id);
+
+        debug_struct
+            .field("node_max_idle_time", &self.node_max_idle_time)
+            .finish()
+    }
+}
+
 const DEFAULT_METASRV_ADDR_PORT: &str = "3002";
 
 impl Default for MetasrvOptions {
@@ -249,6 +291,13 @@ impl MetasrvOptions {
             common_telemetry::debug!("detect local IP is not supported on Android");
         }
     }
+
+    fn sanitize_store_addrs(&self) -> Vec<String> {
+        self.store_addrs
+            .iter()
+            .map(|addr| common_meta::kv_backend::util::sanitize_connection_string(addr))
+            .collect()
+    }
 }
 
 pub struct MetasrvInfo {
@@ -338,6 +387,8 @@ pub struct SelectorContext {
 }
 
 pub type SelectorRef = Arc<dyn Selector<Context = SelectorContext, Output = Vec<Peer>>>;
+pub type RegionStatAwareSelectorRef =
+    Arc<dyn RegionStatAwareSelector<Context = SelectorContext, Output = Vec<(RegionId, Peer)>>>;
 pub type ElectionRef = Arc<dyn Election<Leader = LeaderValue>>;
 
 pub struct MetaStateHandler {

src/meta-srv/src/metasrv/builder.rs

@@ -40,7 +40,7 @@ use common_meta::state_store::KvStateStore;
 use common_meta::wal_options_allocator::{build_kafka_client, build_wal_options_allocator};
 use common_procedure::local::{LocalManager, ManagerConfig};
 use common_procedure::ProcedureManagerRef;
-use common_telemetry::warn;
+use common_telemetry::{info, warn};
 use snafu::{ensure, ResultExt};
 
 use crate::cache_invalidator::MetasrvCacheInvalidator;
@@ -54,16 +54,16 @@ use crate::handler::region_lease_handler::{CustomizedRegionLeaseRenewerRef, Regi
 use crate::handler::{HeartbeatHandlerGroupBuilder, HeartbeatMailbox, Pushers};
 use crate::lease::MetaPeerLookupService;
 use crate::metasrv::{
-    ElectionRef, Metasrv, MetasrvInfo, MetasrvOptions, SelectTarget, SelectorContext, SelectorRef,
-    FLOW_ID_SEQ, TABLE_ID_SEQ,
+    ElectionRef, Metasrv, MetasrvInfo, MetasrvOptions, RegionStatAwareSelectorRef, SelectTarget,
+    SelectorContext, SelectorRef, FLOW_ID_SEQ, TABLE_ID_SEQ,
 };
 use crate::procedure::region_migration::manager::RegionMigrationManager;
 use crate::procedure::region_migration::DefaultContextFactory;
 use crate::procedure::wal_prune::manager::{WalPruneManager, WalPruneTicker};
 use crate::procedure::wal_prune::Context as WalPruneContext;
 use crate::region::supervisor::{
-    HeartbeatAcceptor, RegionFailureDetectorControl, RegionSupervisor, RegionSupervisorTicker,
-    DEFAULT_TICK_INTERVAL,
+    HeartbeatAcceptor, RegionFailureDetectorControl, RegionSupervisor, RegionSupervisorSelector,
+    RegionSupervisorTicker, DEFAULT_TICK_INTERVAL,
 };
 use crate::selector::lease_based::LeaseBasedSelector;
 use crate::selector::round_robin::RoundRobinSelector;
@@ -320,13 +320,24 @@ impl MetasrvBuilder {
             ),
         ));
         region_migration_manager.try_start()?;
+        let region_supervisor_selector = plugins
+            .as_ref()
+            .and_then(|plugins| plugins.get::<RegionStatAwareSelectorRef>());
+
+        let supervisor_selector = match region_supervisor_selector {
+            Some(selector) => {
+                info!("Using region stat aware selector");
+                RegionSupervisorSelector::RegionStatAwareSelector(selector)
+            }
+            None => RegionSupervisorSelector::NaiveSelector(selector.clone()),
+        };
 
         let region_failover_handler = if options.enable_region_failover {
             let region_supervisor = RegionSupervisor::new(
                 rx,
                 options.failure_detector,
                 selector_ctx.clone(),
-                selector.clone(),
+                supervisor_selector,
                 region_migration_manager.clone(),
                 maintenance_mode_manager.clone(),
                 peer_lookup_service.clone(),

src/meta-srv/src/procedure/region_migration.rs

@@ -14,6 +14,7 @@
 
 pub(crate) mod close_downgraded_region;
 pub(crate) mod downgrade_leader_region;
+pub(crate) mod flush_leader_region;
 pub(crate) mod manager;
 pub(crate) mod migration_abort;
 pub(crate) mod migration_end;
@@ -111,6 +112,8 @@ impl PersistentContext {
 pub struct Metrics {
     /// Elapsed time of downgrading region and upgrading region.
     operations_elapsed: Duration,
+    /// Elapsed time of flushing leader region.
+    flush_leader_region_elapsed: Duration,
     /// Elapsed time of downgrading leader region.
     downgrade_leader_region_elapsed: Duration,
     /// Elapsed time of open candidate region.
@@ -121,10 +124,15 @@ pub struct Metrics {
 
 impl Display for Metrics {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let total = self.flush_leader_region_elapsed
+            + self.downgrade_leader_region_elapsed
+            + self.open_candidate_region_elapsed
+            + self.upgrade_candidate_region_elapsed;
         write!(
             f,
-            "operations_elapsed: {:?}, downgrade_leader_region_elapsed: {:?}, open_candidate_region_elapsed: {:?}, upgrade_candidate_region_elapsed: {:?}",
-            self.operations_elapsed,
+            "total: {:?}, flush_leader_region_elapsed: {:?}, downgrade_leader_region_elapsed: {:?}, open_candidate_region_elapsed: {:?}, upgrade_candidate_region_elapsed: {:?}",
+            total,
+            self.flush_leader_region_elapsed,
             self.downgrade_leader_region_elapsed,
             self.open_candidate_region_elapsed,
             self.upgrade_candidate_region_elapsed
@@ -138,6 +146,11 @@ impl Metrics {
         self.operations_elapsed += elapsed;
     }
 
+    /// Updates the elapsed time of flushing leader region.
+    pub fn update_flush_leader_region_elapsed(&mut self, elapsed: Duration) {
+        self.flush_leader_region_elapsed += elapsed;
+    }
+
     /// Updates the elapsed time of downgrading leader region.
     pub fn update_downgrade_leader_region_elapsed(&mut self, elapsed: Duration) {
         self.downgrade_leader_region_elapsed += elapsed;
@@ -156,10 +169,18 @@ impl Metrics {
 
 impl Drop for Metrics {
     fn drop(&mut self) {
-        if !self.operations_elapsed.is_zero() {
+        let total = self.flush_leader_region_elapsed
+            + self.downgrade_leader_region_elapsed
+            + self.open_candidate_region_elapsed
+            + self.upgrade_candidate_region_elapsed;
+        METRIC_META_REGION_MIGRATION_STAGE_ELAPSED
+            .with_label_values(&["total"])
+            .observe(total.as_secs_f64());
+
+        if !self.flush_leader_region_elapsed.is_zero() {
             METRIC_META_REGION_MIGRATION_STAGE_ELAPSED
-                .with_label_values(&["operations"])
-                .observe(self.operations_elapsed.as_secs_f64());
+                .with_label_values(&["flush_leader_region"])
+                .observe(self.flush_leader_region_elapsed.as_secs_f64());
         }
 
         if !self.downgrade_leader_region_elapsed.is_zero() {
@@ -320,6 +341,13 @@ impl Context {
             .update_operations_elapsed(instant.elapsed());
     }
 
+    /// Updates the elapsed time of flushing leader region.
+    pub fn update_flush_leader_region_elapsed(&mut self, instant: Instant) {
+        self.volatile_ctx
+            .metrics
+            .update_flush_leader_region_elapsed(instant.elapsed());
+    }
+
     /// Updates the elapsed time of downgrading leader region.
     pub fn update_downgrade_leader_region_elapsed(&mut self, instant: Instant) {
         self.volatile_ctx
@@ -700,7 +728,8 @@ mod tests {
     use crate::procedure::region_migration::open_candidate_region::OpenCandidateRegion;
     use crate::procedure::region_migration::test_util::*;
     use crate::procedure::test_util::{
-        new_downgrade_region_reply, new_open_region_reply, new_upgrade_region_reply,
+        new_downgrade_region_reply, new_flush_region_reply, new_open_region_reply,
+        new_upgrade_region_reply,
     };
     use crate::service::mailbox::Channel;
 
@@ -1208,6 +1237,15 @@ mod tests {
                     to_peer_id,
                     Arc::new(|id| Ok(new_open_region_reply(id, true, None))),
                 )),
+                Assertion::simple(assert_flush_leader_region, assert_no_persist),
+            ),
+            // Flush Leader Region
+            Step::next(
+                "Should be the flush leader region",
+                Some(mock_datanode_reply(
+                    from_peer_id,
+                    Arc::new(|id| Ok(new_flush_region_reply(id, true, None))),
+                )),
                 Assertion::simple(assert_update_metadata_downgrade, assert_no_persist),
             ),
             // UpdateMetadata::Downgrade

src/meta-srv/src/procedure/region_migration/downgrade_leader_region.rs

@@ -170,7 +170,7 @@ impl DowngradeLeaderRegion {
                 if error.is_some() {
                     return error::RetryLaterSnafu {
                         reason: format!(
-                            "Failed to downgrade the region {} on Datanode {:?}, error: {:?}, elapsed: {:?}",
+                            "Failed to downgrade the region {} on datanode {:?}, error: {:?}, elapsed: {:?}",
                             region_id, leader, error, now.elapsed()
                         ),
                     }
@@ -179,13 +179,14 @@ impl DowngradeLeaderRegion {
 
                 if !exists {
                     warn!(
-                        "Trying to downgrade the region {} on Datanode {}, but region doesn't exist!, elapsed: {:?}",
+                        "Trying to downgrade the region {} on datanode {:?}, but region doesn't exist!, elapsed: {:?}",
                         region_id, leader, now.elapsed()
                     );
                 } else {
                     info!(
-                        "Region {} leader is downgraded, last_entry_id: {:?}, metadata_last_entry_id: {:?}, elapsed: {:?}",
+                        "Region {} leader is downgraded on datanode {:?}, last_entry_id: {:?}, metadata_last_entry_id: {:?}, elapsed: {:?}",
                         region_id,
+                        leader,
                         last_entry_id,
                         metadata_last_entry_id,
                         now.elapsed()

src/meta-srv/src/procedure/region_migration/flush_leader_region.rs

@@ -0,0 +1,285 @@
+// Copyright 2023 Greptime Team
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+use std::any::Any;
+
+use api::v1::meta::MailboxMessage;
+use common_meta::instruction::{Instruction, InstructionReply, SimpleReply};
+use common_procedure::Status;
+use common_telemetry::{info, warn};
+use serde::{Deserialize, Serialize};
+use snafu::{OptionExt, ResultExt};
+use tokio::time::Instant;
+
+use crate::error::{self, Error, Result};
+use crate::handler::HeartbeatMailbox;
+use crate::procedure::region_migration::update_metadata::UpdateMetadata;
+use crate::procedure::region_migration::{Context, State};
+use crate::service::mailbox::Channel;
+
+/// Flushes the leader region before downgrading it.
+///
+/// This can minimize the time window where the region is not writable.
+#[derive(Debug, Serialize, Deserialize)]
+pub struct PreFlushRegion;
+
+#[async_trait::async_trait]
+#[typetag::serde]
+impl State for PreFlushRegion {
+    async fn next(&mut self, ctx: &mut Context) -> Result<(Box<dyn State>, Status)> {
+        let timer = Instant::now();
+        self.flush_region(ctx).await?;
+        ctx.update_flush_leader_region_elapsed(timer);
+        // We intentionally don't update `operations_elapsed` here to prevent
+        // the `next_operation_timeout` from being reduced by the flush operation.
+        // This ensures sufficient time for subsequent critical operations.
+
+        Ok((
+            Box::new(UpdateMetadata::Downgrade),
+            Status::executing(false),
+        ))
+    }
+
+    fn as_any(&self) -> &dyn Any {
+        self
+    }
+}
+
+impl PreFlushRegion {
+    /// Builds flush leader region instruction.
+    fn build_flush_leader_region_instruction(&self, ctx: &Context) -> Instruction {
+        let pc = &ctx.persistent_ctx;
+        let region_id = pc.region_id;
+        Instruction::FlushRegion(region_id)
+    }
+
+    /// Tries to flush a leader region.
+    ///
+    /// Ignore:
+    /// - [PusherNotFound](error::Error::PusherNotFound), The datanode is unreachable.
+    /// - [PushMessage](error::Error::PushMessage), The receiver is dropped.
+    /// - Failed to flush region on the Datanode.
+    ///
+    /// Abort:
+    /// - [MailboxTimeout](error::Error::MailboxTimeout), Timeout.
+    /// - [MailboxReceiver](error::Error::MailboxReceiver), The sender is dropped without sending (impossible).
+    /// - [UnexpectedInstructionReply](error::Error::UnexpectedInstructionReply).
+    /// - [ExceededDeadline](error::Error::ExceededDeadline)
+    /// - Invalid JSON.
+    async fn flush_region(&self, ctx: &mut Context) -> Result<()> {
+        let operation_timeout =
+            ctx.next_operation_timeout()
+                .context(error::ExceededDeadlineSnafu {
+                    operation: "Flush leader region",
+                })?;
+        let flush_instruction = self.build_flush_leader_region_instruction(ctx);
+        let region_id = ctx.persistent_ctx.region_id;
+        let leader = &ctx.persistent_ctx.from_peer;
+
+        let msg = MailboxMessage::json_message(
+            &format!("Flush leader region: {}", region_id),
+            &format!("Metasrv@{}", ctx.server_addr()),
+            &format!("Datanode-{}@{}", leader.id, leader.addr),
+            common_time::util::current_time_millis(),
+            &flush_instruction,
+        )
+        .with_context(|_| error::SerializeToJsonSnafu {
+            input: flush_instruction.to_string(),
+        })?;
+
+        let ch = Channel::Datanode(leader.id);
+        let now = Instant::now();
+        let result = ctx.mailbox.send(&ch, msg, operation_timeout).await;
+
+        match result {
+            Ok(receiver) => match receiver.await? {
+                Ok(msg) => {
+                    let reply = HeartbeatMailbox::json_reply(&msg)?;
+                    info!(
+                        "Received flush leader region reply: {:?}, region: {}, elapsed: {:?}",
+                        reply,
+                        region_id,
+                        now.elapsed()
+                    );
+
+                    let InstructionReply::FlushRegion(SimpleReply { result, error }) = reply else {
+                        return error::UnexpectedInstructionReplySnafu {
+                            mailbox_message: msg.to_string(),
+                            reason: "expect flush region reply",
+                        }
+                        .fail();
+                    };
+
+                    if error.is_some() {
+                        warn!(
+                            "Failed to flush leader region {} on datanode {:?}, error: {:?}. Skip flush operation.",
+                            region_id, leader, error
+                        );
+                    } else if result {
+                        info!(
+                            "The flush leader region {} on datanode {:?} is successful, elapsed: {:?}",
+                            region_id,
+                            leader,
+                            now.elapsed()
+                        );
+                    }
+
+                    Ok(())
+                }
+                Err(Error::MailboxTimeout { .. }) => error::ExceededDeadlineSnafu {
+                    operation: "Flush leader region",
+                }
+                .fail(),
+                Err(err) => Err(err),
+            },
+            Err(Error::PusherNotFound { .. }) => {
+                warn!(
+                    "Failed to flush leader region({}), the datanode({}) is unreachable(PusherNotFound). Skip flush operation.",
+                    region_id,
+                    leader
+                );
+                Ok(())
+            }
+            Err(err) => Err(err),
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use std::assert_matches::assert_matches;
+
+    use store_api::storage::RegionId;
+
+    use super::*;
+    use crate::procedure::region_migration::test_util::{self, TestingEnv};
+    use crate::procedure::region_migration::{ContextFactory, PersistentContext};
+    use crate::procedure::test_util::{
+        new_close_region_reply, new_flush_region_reply, send_mock_reply,
+    };
+
+    fn new_persistent_context() -> PersistentContext {
+        test_util::new_persistent_context(1, 2, RegionId::new(1024, 1))
+    }
+
+    #[tokio::test]
+    async fn test_datanode_is_unreachable() {
+        let state = PreFlushRegion;
+        // from_peer: 1
+        // to_peer: 2
+        let persistent_context = new_persistent_context();
+        let env = TestingEnv::new();
+        let mut ctx = env.context_factory().new_context(persistent_context);
+        // Should be ok, if leader region is unreachable. it will skip flush operation.
+        state.flush_region(&mut ctx).await.unwrap();
+    }
+
+    #[tokio::test]
+    async fn test_unexpected_instruction_reply() {
+        common_telemetry::init_default_ut_logging();
+        let state = PreFlushRegion;
+        // from_peer: 1
+        // to_peer: 2
+        let persistent_context = new_persistent_context();
+        let from_peer_id = persistent_context.from_peer.id;
+        let mut env = TestingEnv::new();
+        let mut ctx = env.context_factory().new_context(persistent_context);
+        let mailbox_ctx = env.mailbox_context();
+        let mailbox = mailbox_ctx.mailbox().clone();
+        let (tx, rx) = tokio::sync::mpsc::channel(1);
+        mailbox_ctx
+            .insert_heartbeat_response_receiver(Channel::Datanode(from_peer_id), tx)
+            .await;
+        // Sends an incorrect reply.
+        send_mock_reply(mailbox, rx, |id| Ok(new_close_region_reply(id)));
+        let err = state.flush_region(&mut ctx).await.unwrap_err();
+        assert_matches!(err, Error::UnexpectedInstructionReply { .. });
+        assert!(!err.is_retryable());
+    }
+
+    #[tokio::test]
+    async fn test_instruction_exceeded_deadline() {
+        let state = PreFlushRegion;
+        // from_peer: 1
+        // to_peer: 2
+        let persistent_context = new_persistent_context();
+        let from_peer_id = persistent_context.from_peer.id;
+        let mut env = TestingEnv::new();
+        let mut ctx = env.context_factory().new_context(persistent_context);
+        let mailbox_ctx = env.mailbox_context();
+        let mailbox = mailbox_ctx.mailbox().clone();
+        let (tx, rx) = tokio::sync::mpsc::channel(1);
+        mailbox_ctx
+            .insert_heartbeat_response_receiver(Channel::Datanode(from_peer_id), tx)
+            .await;
+        // Sends an timeout error.
+        send_mock_reply(mailbox, rx, |id| {
+            Err(error::MailboxTimeoutSnafu { id }.build())
+        });
+
+        let err = state.flush_region(&mut ctx).await.unwrap_err();
+        assert_matches!(err, Error::ExceededDeadline { .. });
+        assert!(!err.is_retryable());
+    }
+
+    #[tokio::test]
+    async fn test_flush_region_failed() {
+        common_telemetry::init_default_ut_logging();
+        let state = PreFlushRegion;
+        // from_peer: 1
+        // to_peer: 2
+        let persistent_context = new_persistent_context();
+        let from_peer_id = persistent_context.from_peer.id;
+        let mut env = TestingEnv::new();
+        let mut ctx = env.context_factory().new_context(persistent_context);
+        let mailbox_ctx = env.mailbox_context();
+        let mailbox = mailbox_ctx.mailbox().clone();
+        let (tx, rx) = tokio::sync::mpsc::channel(1);
+        mailbox_ctx
+            .insert_heartbeat_response_receiver(Channel::Datanode(from_peer_id), tx)
+            .await;
+        send_mock_reply(mailbox, rx, |id| {
+            Ok(new_flush_region_reply(
+                id,
+                false,
+                Some("test mocked".to_string()),
+            ))
+        });
+        // Should be ok, if flush leader region failed. it will skip flush operation.
+        state.flush_region(&mut ctx).await.unwrap();
+    }
+
+    #[tokio::test]
+    async fn test_next_update_metadata_downgrade_state() {
+        common_telemetry::init_default_ut_logging();
+        let mut state = PreFlushRegion;
+        // from_peer: 1
+        // to_peer: 2
+        let persistent_context = new_persistent_context();
+        let from_peer_id = persistent_context.from_peer.id;
+        let mut env = TestingEnv::new();
+        let mut ctx = env.context_factory().new_context(persistent_context);
+        let mailbox_ctx = env.mailbox_context();
+        let mailbox = mailbox_ctx.mailbox().clone();
+        let (tx, rx) = tokio::sync::mpsc::channel(1);
+        mailbox_ctx
+            .insert_heartbeat_response_receiver(Channel::Datanode(from_peer_id), tx)
+            .await;
+        send_mock_reply(mailbox, rx, |id| Ok(new_flush_region_reply(id, true, None)));
+        let (next, _) = state.next(&mut ctx).await.unwrap();
+
+        let update_metadata = next.as_any().downcast_ref::<UpdateMetadata>().unwrap();
+        assert_matches!(update_metadata, UpdateMetadata::Downgrade);
+    }
+}

src/meta-srv/src/procedure/region_migration/open_candidate_region.rs

@@ -28,7 +28,7 @@ use tokio::time::Instant;
 
 use crate::error::{self, Result};
 use crate::handler::HeartbeatMailbox;
-use crate::procedure::region_migration::update_metadata::UpdateMetadata;
+use crate::procedure::region_migration::flush_leader_region::PreFlushRegion;
 use crate::procedure::region_migration::{Context, State};
 use crate::service::mailbox::Channel;
 
@@ -47,10 +47,7 @@ impl State for OpenCandidateRegion {
         self.open_candidate_region(ctx, instruction).await?;
         ctx.update_open_candidate_region_elapsed(now);
 
-        Ok((
-            Box::new(UpdateMetadata::Downgrade),
-            Status::executing(false),
-        ))
+        Ok((Box::new(PreFlushRegion), Status::executing(false)))
     }
 
     fn as_any(&self) -> &dyn Any {
@@ -399,7 +396,7 @@ mod tests {
     }
 
     #[tokio::test]
-    async fn test_next_update_metadata_downgrade_state() {
+    async fn test_next_flush_leader_region_state() {
         let mut state = Box::new(OpenCandidateRegion);
         // from_peer: 1
         // to_peer: 2
@@ -445,8 +442,7 @@ mod tests {
             (to_peer_id, region_id)
         );
 
-        let update_metadata = next.as_any().downcast_ref::<UpdateMetadata>().unwrap();
-
-        assert_matches!(update_metadata, UpdateMetadata::Downgrade);
+        let flush_leader_region = next.as_any().downcast_ref::<PreFlushRegion>().unwrap();
+        assert_matches!(flush_leader_region, PreFlushRegion);
     }
 }

src/meta-srv/src/procedure/region_migration/test_util.rs

@@ -44,6 +44,7 @@ use crate::error::{self, Error, Result};
 use crate::metasrv::MetasrvInfo;
 use crate::procedure::region_migration::close_downgraded_region::CloseDowngradedRegion;
 use crate::procedure::region_migration::downgrade_leader_region::DowngradeLeaderRegion;
+use crate::procedure::region_migration::flush_leader_region::PreFlushRegion;
 use crate::procedure::region_migration::manager::RegionMigrationProcedureTracker;
 use crate::procedure::region_migration::migration_abort::RegionMigrationAbort;
 use crate::procedure::region_migration::migration_end::RegionMigrationEnd;
@@ -415,6 +416,11 @@ pub(crate) fn assert_open_candidate_region(next: &dyn State) {
     let _ = next.as_any().downcast_ref::<OpenCandidateRegion>().unwrap();
 }
 
+/// Asserts the [State] should be [FlushLeaderRegion].
+pub(crate) fn assert_flush_leader_region(next: &dyn State) {
+    let _ = next.as_any().downcast_ref::<PreFlushRegion>().unwrap();
+}
+
 /// Asserts the [State] should be [UpdateMetadata::Downgrade].
 pub(crate) fn assert_update_metadata_downgrade(next: &dyn State) {
     let state = next.as_any().downcast_ref::<UpdateMetadata>().unwrap();

src/meta-srv/src/procedure/test_util.rs

@@ -101,6 +101,24 @@ pub fn new_open_region_reply(id: u64, result: bool, error: Option<String>) -> Ma
     }
 }
 
+/// Generates a [InstructionReply::FlushRegion] reply.
+pub fn new_flush_region_reply(id: u64, result: bool, error: Option<String>) -> MailboxMessage {
+    MailboxMessage {
+        id,
+        subject: "mock".to_string(),
+        from: "datanode".to_string(),
+        to: "meta".to_string(),
+        timestamp_millis: current_time_millis(),
+        payload: Some(Payload::Json(
+            serde_json::to_string(&InstructionReply::FlushRegion(SimpleReply {
+                result,
+                error,
+            }))
+            .unwrap(),
+        )),
+    }
+}
+
 /// Generates a [InstructionReply::CloseRegion] reply.
 pub fn new_close_region_reply(id: u64) -> MailboxMessage {
     MailboxMessage {

src/meta-srv/src/procedure/wal_prune.rs

@@ -181,7 +181,7 @@ impl WalPruneProcedure {
         let peer_and_instructions = peer_region_ids_map
             .into_iter()
             .map(|(peer, region_ids)| {
-                let flush_instruction = Instruction::FlushRegion(FlushRegions { region_ids });
+                let flush_instruction = Instruction::FlushRegions(FlushRegions { region_ids });
                 (peer.clone(), flush_instruction)
             })
             .collect();
@@ -536,7 +536,7 @@ mod tests {
         let msg = resp.mailbox_message.unwrap();
         let flush_instruction = HeartbeatMailbox::json_instruction(&msg).unwrap();
         let mut flush_requested_region_ids = match flush_instruction {
-            Instruction::FlushRegion(FlushRegions { region_ids, .. }) => region_ids,
+            Instruction::FlushRegions(FlushRegions { region_ids, .. }) => region_ids,
             _ => unreachable!(),
         };
         let sorted_region_ids = region_ids

src/meta-srv/src/region/supervisor.rs

@@ -22,20 +22,20 @@ use common_meta::datanode::Stat;
 use common_meta::ddl::{DetectingRegion, RegionFailureDetectorController};
 use common_meta::key::maintenance::MaintenanceModeManagerRef;
 use common_meta::leadership_notifier::LeadershipChangeListener;
-use common_meta::peer::PeerLookupServiceRef;
+use common_meta::peer::{Peer, PeerLookupServiceRef};
 use common_meta::DatanodeId;
 use common_runtime::JoinHandle;
 use common_telemetry::{debug, error, info, warn};
 use common_time::util::current_time_millis;
 use error::Error::{LeaderPeerChanged, MigrationRunning, TableRouteNotFound};
-use snafu::{OptionExt, ResultExt};
+use snafu::{ensure, OptionExt, ResultExt};
 use store_api::storage::RegionId;
 use tokio::sync::mpsc::{Receiver, Sender};
 use tokio::time::{interval, MissedTickBehavior};
 
 use crate::error::{self, Result};
 use crate::failure_detector::PhiAccrualFailureDetectorOptions;
-use crate::metasrv::{SelectorContext, SelectorRef};
+use crate::metasrv::{RegionStatAwareSelectorRef, SelectTarget, SelectorContext, SelectorRef};
 use crate::procedure::region_migration::manager::RegionMigrationManagerRef;
 use crate::procedure::region_migration::{
     RegionMigrationProcedureTask, DEFAULT_REGION_MIGRATION_TIMEOUT,
@@ -203,6 +203,12 @@ pub type RegionSupervisorRef = Arc<RegionSupervisor>;
 /// The default tick interval.
 pub const DEFAULT_TICK_INTERVAL: Duration = Duration::from_secs(1);
 
+/// Selector for region supervisor.
+pub enum RegionSupervisorSelector {
+    NaiveSelector(SelectorRef),
+    RegionStatAwareSelector(RegionStatAwareSelectorRef),
+}
+
 /// The [`RegionSupervisor`] is used to detect Region failures
 /// and initiate Region failover upon detection, ensuring uninterrupted region service.
 pub struct RegionSupervisor {
@@ -215,7 +221,7 @@ pub struct RegionSupervisor {
     /// The context of [`SelectorRef`]
     selector_context: SelectorContext,
     /// Candidate node selector.
-    selector: SelectorRef,
+    selector: RegionSupervisorSelector,
     /// Region migration manager.
     region_migration_manager: RegionMigrationManagerRef,
     /// The maintenance mode manager.
@@ -288,7 +294,7 @@ impl RegionSupervisor {
         event_receiver: Receiver<Event>,
         options: PhiAccrualFailureDetectorOptions,
         selector_context: SelectorContext,
-        selector: SelectorRef,
+        selector: RegionSupervisorSelector,
         region_migration_manager: RegionMigrationManagerRef,
         maintenance_mode_manager: MaintenanceModeManagerRef,
         peer_lookup: PeerLookupServiceRef,
@@ -362,6 +368,7 @@ impl RegionSupervisor {
             }
         }
 
+        // Extracts regions that are migrating(failover), which means they are already being triggered failover.
         let migrating_regions = regions
             .extract_if(.., |(_, region_id)| {
                 self.region_migration_manager.tracker().contains(*region_id)
@@ -374,10 +381,43 @@ impl RegionSupervisor {
             );
         }
 
-        warn!("Detects region failures: {:?}", regions);
+        if regions.is_empty() {
+            // If all detected regions are failover or migrating, just return.
+            return;
+        }
+
+        let mut grouped_regions: HashMap<u64, Vec<RegionId>> =
+            HashMap::with_capacity(regions.len());
         for (datanode_id, region_id) in regions {
-            if let Err(err) = self.do_failover(datanode_id, region_id).await {
-                error!(err; "Failed to execute region failover for region: {region_id}, datanode: {datanode_id}");
+            grouped_regions
+                .entry(datanode_id)
+                .or_default()
+                .push(region_id);
+        }
+
+        for (datanode_id, regions) in grouped_regions {
+            warn!(
+                "Detects region failures on datanode: {}, regions: {:?}",
+                datanode_id, regions
+            );
+            // We can't use `grouped_regions.keys().cloned().collect::<Vec<_>>()` here
+            // because there may be false positives in failure detection on the datanode.
+            // So we only consider the datanode that reports the failure.
+            let failed_datanodes = [datanode_id];
+            match self
+                .generate_failover_tasks(datanode_id, &regions, &failed_datanodes)
+                .await
+            {
+                Ok(tasks) => {
+                    for (task, count) in tasks {
+                        let region_id = task.region_id;
+                        let datanode_id = task.from_peer.id;
+                        if let Err(err) = self.do_failover(task, count).await {
+                            error!(err; "Failed to execute region failover for region: {}, datanode: {}", region_id, datanode_id);
+                        }
+                    }
+                }
+                Err(err) => error!(err; "Failed to generate failover tasks"),
             }
         }
     }
@@ -389,49 +429,107 @@ impl RegionSupervisor {
             .context(error::MaintenanceModeManagerSnafu)
     }
 
-    async fn do_failover(&mut self, datanode_id: DatanodeId, region_id: RegionId) -> Result<()> {
-        let count = *self
-            .failover_counts
-            .entry((datanode_id, region_id))
-            .and_modify(|count| *count += 1)
-            .or_insert(1);
+    async fn select_peers(
+        &self,
+        from_peer_id: DatanodeId,
+        regions: &[RegionId],
+        failure_datanodes: &[DatanodeId],
+    ) -> Result<Vec<(RegionId, Peer)>> {
+        let exclude_peer_ids = HashSet::from_iter(failure_datanodes.iter().cloned());
+        match &self.selector {
+            RegionSupervisorSelector::NaiveSelector(selector) => {
+                let opt = SelectorOptions {
+                    min_required_items: regions.len(),
+                    allow_duplication: true,
+                    exclude_peer_ids,
+                };
+                let peers = selector.select(&self.selector_context, opt).await?;
+                ensure!(
+                    peers.len() == regions.len(),
+                    error::NoEnoughAvailableNodeSnafu {
+                        required: regions.len(),
+                        available: peers.len(),
+                        select_target: SelectTarget::Datanode,
+                    }
+                );
+                let region_peers = regions
+                    .iter()
+                    .zip(peers)
+                    .map(|(region_id, peer)| (*region_id, peer))
+                    .collect::<Vec<_>>();
+
+                Ok(region_peers)
+            }
+            RegionSupervisorSelector::RegionStatAwareSelector(selector) => {
+                let peers = selector
+                    .select(
+                        &self.selector_context,
+                        from_peer_id,
+                        regions,
+                        exclude_peer_ids,
+                    )
+                    .await?;
+                ensure!(
+                    peers.len() == regions.len(),
+                    error::NoEnoughAvailableNodeSnafu {
+                        required: regions.len(),
+                        available: peers.len(),
+                        select_target: SelectTarget::Datanode,
+                    }
+                );
+
+                Ok(peers)
+            }
+        }
+    }
+
+    async fn generate_failover_tasks(
+        &mut self,
+        from_peer_id: DatanodeId,
+        regions: &[RegionId],
+        failed_datanodes: &[DatanodeId],
+    ) -> Result<Vec<(RegionMigrationProcedureTask, u32)>> {
+        let mut tasks = Vec::with_capacity(regions.len());
         let from_peer = self
             .peer_lookup
-            .datanode(datanode_id)
+            .datanode(from_peer_id)
             .await
             .context(error::LookupPeerSnafu {
-                peer_id: datanode_id,
+                peer_id: from_peer_id,
             })?
             .context(error::PeerUnavailableSnafu {
-                peer_id: datanode_id,
+                peer_id: from_peer_id,
             })?;
-        let mut peers = self
-            .selector
-            .select(
-                &self.selector_context,
-                SelectorOptions {
-                    min_required_items: 1,
-                    allow_duplication: false,
-                    exclude_peer_ids: HashSet::from([from_peer.id]),
-                },
-            )
+        let region_peers = self
+            .select_peers(from_peer_id, regions, failed_datanodes)
             .await?;
-        let to_peer = peers.remove(0);
-        if to_peer.id == from_peer.id {
-            warn!(
-                "Skip failover for region: {region_id}, from_peer: {from_peer}, trying to failover to the same peer."
-            );
-            return Ok(());
+
+        for (region_id, peer) in region_peers {
+            let count = *self
+                .failover_counts
+                .entry((from_peer_id, region_id))
+                .and_modify(|count| *count += 1)
+                .or_insert(1);
+            let task = RegionMigrationProcedureTask {
+                region_id,
+                from_peer: from_peer.clone(),
+                to_peer: peer,
+                timeout: DEFAULT_REGION_MIGRATION_TIMEOUT * count,
+            };
+            tasks.push((task, count));
         }
+
+        Ok(tasks)
+    }
+
+    async fn do_failover(&mut self, task: RegionMigrationProcedureTask, count: u32) -> Result<()> {
+        let from_peer_id = task.from_peer.id;
+        let region_id = task.region_id;
+
         info!(
-            "Failover for region: {region_id}, from_peer: {from_peer}, to_peer: {to_peer}, tries: {count}"
+            "Failover for region: {}, from_peer: {}, to_peer: {}, timeout: {:?}, tries: {}",
+            task.region_id, task.from_peer, task.to_peer, task.timeout, count
         );
-        let task = RegionMigrationProcedureTask {
-            region_id,
-            from_peer,
-            to_peer,
-            timeout: DEFAULT_REGION_MIGRATION_TIMEOUT * count,
-        };
 
         if let Err(err) = self.region_migration_manager.submit_procedure(task).await {
             return match err {
@@ -439,25 +537,25 @@ impl RegionSupervisor {
                 MigrationRunning { .. } => {
                     info!(
                         "Another region migration is running, skip failover for region: {}, datanode: {}",
-                        region_id, datanode_id
+                        region_id, from_peer_id
                     );
                     Ok(())
                 }
                 TableRouteNotFound { .. } => {
-                    self.deregister_failure_detectors(vec![(datanode_id, region_id)])
+                    self.deregister_failure_detectors(vec![(from_peer_id, region_id)])
                         .await;
                     info!(
                         "Table route is not found, the table is dropped, removed failover detector for region: {}, datanode: {}",
-                        region_id, datanode_id
+                        region_id, from_peer_id
                     );
                     Ok(())
                 }
                 LeaderPeerChanged { .. } => {
-                    self.deregister_failure_detectors(vec![(datanode_id, region_id)])
+                    self.deregister_failure_detectors(vec![(from_peer_id, region_id)])
                         .await;
                     info!(
                         "Region's leader peer changed, removed failover detector for region: {}, datanode: {}",
-                        region_id, datanode_id
+                        region_id, from_peer_id
                     );
                     Ok(())
                 }
@@ -521,6 +619,7 @@ pub(crate) mod tests {
     use tokio::sync::oneshot;
     use tokio::time::sleep;
 
+    use super::RegionSupervisorSelector;
     use crate::procedure::region_migration::manager::RegionMigrationManager;
     use crate::procedure::region_migration::test_util::TestingEnv;
     use crate::region::supervisor::{
@@ -548,7 +647,7 @@ pub(crate) mod tests {
                 rx,
                 Default::default(),
                 selector_context,
-                selector,
+                RegionSupervisorSelector::NaiveSelector(selector),
                 region_migration_manager,
                 maintenance_mode_manager,
                 peer_lookup,

src/meta-srv/src/selector.rs

@@ -23,6 +23,7 @@ pub mod weighted_choose;
 use std::collections::HashSet;
 
 use serde::{Deserialize, Serialize};
+use store_api::storage::RegionId;
 use strum::AsRefStr;
 
 use crate::error;
@@ -36,6 +37,24 @@ pub trait Selector: Send + Sync {
     async fn select(&self, ctx: &Self::Context, opts: SelectorOptions) -> Result<Self::Output>;
 }
 
+/// A selector that aware of region statistics
+///
+/// It selects the best destination peer for a list of regions.
+/// The selection is based on the region statistics, such as the region leader's write throughput.
+#[async_trait::async_trait]
+pub trait RegionStatAwareSelector: Send + Sync {
+    type Context;
+    type Output;
+
+    async fn select(
+        &self,
+        ctx: &Self::Context,
+        from_peer_id: u64,
+        region_ids: &[RegionId],
+        exclude_peer_ids: HashSet<u64>,
+    ) -> Result<Self::Output>;
+}
+
 #[derive(Debug)]
 pub struct SelectorOptions {
     /// Minimum number of selected results.

src/metric-engine/src/engine.rs

@@ -42,11 +42,11 @@ pub(crate) use state::MetricEngineState;
 use store_api::metadata::RegionMetadataRef;
 use store_api::metric_engine_consts::METRIC_ENGINE_NAME;
 use store_api::region_engine::{
-    RegionEngine, RegionManifestInfo, RegionRole, RegionScannerRef, RegionStatistic,
-    SetRegionRoleStateResponse, SetRegionRoleStateSuccess, SettableRegionRoleState,
-    SyncManifestResponse,
+    BatchResponses, RegionEngine, RegionManifestInfo, RegionRole, RegionScannerRef,
+    RegionStatistic, SetRegionRoleStateResponse, SetRegionRoleStateSuccess,
+    SettableRegionRoleState, SyncManifestResponse,
 };
-use store_api::region_request::{BatchRegionDdlRequest, RegionRequest};
+use store_api::region_request::{BatchRegionDdlRequest, RegionOpenRequest, RegionRequest};
 use store_api::storage::{RegionId, ScanRequest, SequenceNumber};
 
 use crate::config::EngineConfig;
@@ -131,6 +131,17 @@ impl RegionEngine for MetricEngine {
         METRIC_ENGINE_NAME
     }
 
+    async fn handle_batch_open_requests(
+        &self,
+        parallelism: usize,
+        requests: Vec<(RegionId, RegionOpenRequest)>,
+    ) -> Result<BatchResponses, BoxedError> {
+        self.inner
+            .handle_batch_open_requests(parallelism, requests)
+            .await
+            .map_err(BoxedError::new)
+    }
+
     async fn handle_batch_ddl_requests(
         &self,
         batch_request: BatchRegionDdlRequest,

src/metric-engine/src/engine/open.rs

@@ -14,24 +14,80 @@
 
 //! Open a metric region.
 
+use std::collections::HashSet;
+
 use common_telemetry::info;
 use mito2::engine::MITO_ENGINE_NAME;
 use object_store::util::join_dir;
 use snafu::{OptionExt, ResultExt};
 use store_api::codec::PrimaryKeyEncoding;
 use store_api::metric_engine_consts::{DATA_REGION_SUBDIR, METADATA_REGION_SUBDIR};
-use store_api::region_engine::RegionEngine;
+use store_api::region_engine::{BatchResponses, RegionEngine};
 use store_api::region_request::{AffectedRows, RegionOpenRequest, RegionRequest};
 use store_api::storage::RegionId;
 
 use crate::engine::create::region_options_for_metadata_region;
 use crate::engine::options::{set_data_region_options, PhysicalRegionOptions};
 use crate::engine::MetricEngineInner;
-use crate::error::{OpenMitoRegionSnafu, PhysicalRegionNotFoundSnafu, Result};
+use crate::error::{
+    BatchOpenMitoRegionSnafu, OpenMitoRegionSnafu, PhysicalRegionNotFoundSnafu, Result,
+};
 use crate::metrics::{LOGICAL_REGION_COUNT, PHYSICAL_REGION_COUNT};
 use crate::utils;
 
 impl MetricEngineInner {
+    pub async fn handle_batch_open_requests(
+        &self,
+        parallelism: usize,
+        requests: Vec<(RegionId, RegionOpenRequest)>,
+    ) -> Result<BatchResponses> {
+        // We need to open metadata region and data region for each request.
+        let mut all_requests = Vec::with_capacity(requests.len() * 2);
+        let mut physical_region_ids = Vec::with_capacity(requests.len());
+        let mut data_region_ids = HashSet::with_capacity(requests.len());
+
+        for (region_id, request) in requests {
+            if !request.is_physical_table() {
+                continue;
+            }
+            let physical_region_options = PhysicalRegionOptions::try_from(&request.options)?;
+            let metadata_region_id = utils::to_metadata_region_id(region_id);
+            let data_region_id = utils::to_data_region_id(region_id);
+            let (open_metadata_region_request, open_data_region_request) =
+                self.transform_open_physical_region_request(request);
+            all_requests.push((metadata_region_id, open_metadata_region_request));
+            all_requests.push((data_region_id, open_data_region_request));
+            physical_region_ids.push((region_id, physical_region_options));
+            data_region_ids.insert(data_region_id);
+        }
+
+        let results = self
+            .mito
+            .handle_batch_open_requests(parallelism, all_requests)
+            .await
+            .context(BatchOpenMitoRegionSnafu {})?
+            .into_iter()
+            .filter(|(region_id, _)| data_region_ids.contains(region_id))
+            .collect::<Vec<_>>();
+
+        for (physical_region_id, physical_region_options) in physical_region_ids {
+            let primary_key_encoding = self
+                .mito
+                .get_primary_key_encoding(physical_region_id)
+                .context(PhysicalRegionNotFoundSnafu {
+                    region_id: physical_region_id,
+                })?;
+            self.recover_states(
+                physical_region_id,
+                primary_key_encoding,
+                physical_region_options,
+            )
+            .await?;
+        }
+
+        Ok(results)
+    }
+
     /// Open a metric region.
     ///
     /// Only open requests to a physical region matter. Those to logical regions are
@@ -69,12 +125,15 @@ impl MetricEngineInner {
         }
     }
 
-    /// Invokes mito engine to open physical regions (data and metadata).
-    async fn open_physical_region(
+    /// Transform the open request to open metadata region and data region.
+    ///
+    /// Returns:
+    /// - The open request for metadata region.
+    /// - The open request for data region.
+    fn transform_open_physical_region_request(
         &self,
-        region_id: RegionId,
         request: RegionOpenRequest,
-    ) -> Result<AffectedRows> {
+    ) -> (RegionOpenRequest, RegionOpenRequest) {
         let metadata_region_dir = join_dir(&request.region_dir, METADATA_REGION_SUBDIR);
         let data_region_dir = join_dir(&request.region_dir, DATA_REGION_SUBDIR);
 
@@ -98,8 +157,19 @@ impl MetricEngineInner {
             skip_wal_replay: request.skip_wal_replay,
         };
 
+        (open_metadata_region_request, open_data_region_request)
+    }
+
+    /// Invokes mito engine to open physical regions (data and metadata).
+    async fn open_physical_region(
+        &self,
+        region_id: RegionId,
+        request: RegionOpenRequest,
+    ) -> Result<AffectedRows> {
         let metadata_region_id = utils::to_metadata_region_id(region_id);
         let data_region_id = utils::to_data_region_id(region_id);
+        let (open_metadata_region_request, open_data_region_request) =
+            self.transform_open_physical_region_request(request);
 
         self.mito
             .handle_request(

src/metric-engine/src/error.rs

@@ -42,6 +42,13 @@ pub enum Error {
         location: Location,
     },
 
+    #[snafu(display("Failed to batch open mito region"))]
+    BatchOpenMitoRegion {
+        source: BoxedError,
+        #[snafu(implicit)]
+        location: Location,
+    },
+
     #[snafu(display("Failed to close mito region, region id: {}", region_id))]
     CloseMitoRegion {
         region_id: RegionId,
@@ -337,7 +344,8 @@ impl ErrorExt for Error {
             | MitoCatchupOperation { source, .. }
             | MitoFlushOperation { source, .. }
             | MitoDeleteOperation { source, .. }
-            | MitoSyncOperation { source, .. } => source.status_code(),
+            | MitoSyncOperation { source, .. }
+            | BatchOpenMitoRegion { source, .. } => source.status_code(),
 
             EncodePrimaryKey { source, .. } => source.status_code(),
 

src/mito2/src/memtable/partition_tree.rs

@@ -302,7 +302,10 @@ impl PartitionTreeMemtable {
     fn update_stats(&self, metrics: &WriteMetrics) {
         // Only let the tracker tracks value bytes.
         self.alloc_tracker.on_allocation(metrics.value_bytes);
-        metrics.update_timestamp_range(&self.max_timestamp, &self.min_timestamp);
+        self.max_timestamp
+            .fetch_max(metrics.max_ts, Ordering::SeqCst);
+        self.min_timestamp
+            .fetch_min(metrics.min_ts, Ordering::SeqCst);
     }
 }
 

src/mito2/src/memtable/stats.rs

@@ -14,8 +14,6 @@
 
 //! Internal metrics of the memtable.
 
-use std::sync::atomic::{AtomicI64, Ordering};
-
 /// Metrics of writing memtables.
 pub(crate) struct WriteMetrics {
     /// Size allocated by keys.
@@ -28,51 +26,6 @@ pub(crate) struct WriteMetrics {
     pub(crate) max_ts: i64,
 }
 
-impl WriteMetrics {
-    /// Update the min/max timestamp range according to current write metric.
-    pub(crate) fn update_timestamp_range(&self, prev_max_ts: &AtomicI64, prev_min_ts: &AtomicI64) {
-        loop {
-            let current_min = prev_min_ts.load(Ordering::Relaxed);
-            if self.min_ts >= current_min {
-                break;
-            }
-
-            let Err(updated) = prev_min_ts.compare_exchange(
-                current_min,
-                self.min_ts,
-                Ordering::Relaxed,
-                Ordering::Relaxed,
-            ) else {
-                break;
-            };
-
-            if updated == self.min_ts {
-                break;
-            }
-        }
-
-        loop {
-            let current_max = prev_max_ts.load(Ordering::Relaxed);
-            if self.max_ts <= current_max {
-                break;
-            }
-
-            let Err(updated) = prev_max_ts.compare_exchange(
-                current_max,
-                self.max_ts,
-                Ordering::Relaxed,
-                Ordering::Relaxed,
-            ) else {
-                break;
-            };
-
-            if updated == self.max_ts {
-                break;
-            }
-        }
-    }
-}
-
 impl Default for WriteMetrics {
     fn default() -> Self {
         Self {

src/mito2/src/memtable/time_series.rs

@@ -147,7 +147,8 @@ impl TimeSeriesMemtable {
     fn update_stats(&self, stats: WriteMetrics) {
         self.alloc_tracker
             .on_allocation(stats.key_bytes + stats.value_bytes);
-        stats.update_timestamp_range(&self.max_timestamp, &self.min_timestamp);
+        self.max_timestamp.fetch_max(stats.max_ts, Ordering::SeqCst);
+        self.min_timestamp.fetch_min(stats.min_ts, Ordering::SeqCst);
     }
 
     fn write_key_value(&self, kv: KeyValue, stats: &mut WriteMetrics) -> Result<()> {

src/mito2/src/read/scan_region.rs

@@ -322,13 +322,10 @@ impl ScanRegion {
         let memtables: Vec<_> = memtables
             .into_iter()
             .filter(|mem| {
-                if mem.is_empty() {
+                // check if memtable is empty by reading stats.
+                let Some((start, end)) = mem.stats().time_range() else {
                     return false;
-                }
-                let stats = mem.stats();
-                // Safety: the memtable is not empty.
-                let (start, end) = stats.time_range().unwrap();
-
+                };
                 // The time range of the memtable is inclusive.
                 let memtable_range = TimestampRange::new_inclusive(Some(start), Some(end));
                 memtable_range.intersects(&time_range)

src/mito2/src/sst/parquet/format.rs

@@ -134,6 +134,7 @@ impl WriteFormat {
 
 /// Helper for reading the SST format.
 pub struct ReadFormat {
+    /// The metadata stored in the SST.
     metadata: RegionMetadataRef,
     /// SST file schema.
     arrow_schema: SchemaRef,
@@ -305,17 +306,23 @@ impl ReadFormat {
         &self,
         row_groups: &[impl Borrow<RowGroupMetaData>],
         column_id: ColumnId,
-    ) -> Option<ArrayRef> {
-        let column = self.metadata.column_by_id(column_id)?;
+    ) -> StatValues {
+        let Some(column) = self.metadata.column_by_id(column_id) else {
+            // No such column in the SST.
+            return StatValues::NoColumn;
+        };
         match column.semantic_type {
             SemanticType::Tag => self.tag_values(row_groups, column, true),
             SemanticType::Field => {
-                let index = self.field_id_to_index.get(&column_id)?;
-                Self::column_values(row_groups, column, *index, true)
+                // Safety: `field_id_to_index` is initialized by the semantic type.
+                let index = self.field_id_to_index.get(&column_id).unwrap();
+                let stats = Self::column_values(row_groups, column, *index, true);
+                StatValues::from_stats_opt(stats)
             }
             SemanticType::Timestamp => {
                 let index = self.time_index_position();
-                Self::column_values(row_groups, column, index, true)
+                let stats = Self::column_values(row_groups, column, index, true);
+                StatValues::from_stats_opt(stats)
             }
         }
     }
@@ -325,17 +332,23 @@ impl ReadFormat {
         &self,
         row_groups: &[impl Borrow<RowGroupMetaData>],
         column_id: ColumnId,
-    ) -> Option<ArrayRef> {
-        let column = self.metadata.column_by_id(column_id)?;
+    ) -> StatValues {
+        let Some(column) = self.metadata.column_by_id(column_id) else {
+            // No such column in the SST.
+            return StatValues::NoColumn;
+        };
         match column.semantic_type {
             SemanticType::Tag => self.tag_values(row_groups, column, false),
             SemanticType::Field => {
-                let index = self.field_id_to_index.get(&column_id)?;
-                Self::column_values(row_groups, column, *index, false)
+                // Safety: `field_id_to_index` is initialized by the semantic type.
+                let index = self.field_id_to_index.get(&column_id).unwrap();
+                let stats = Self::column_values(row_groups, column, *index, false);
+                StatValues::from_stats_opt(stats)
             }
             SemanticType::Timestamp => {
                 let index = self.time_index_position();
-                Self::column_values(row_groups, column, index, false)
+                let stats = Self::column_values(row_groups, column, index, false);
+                StatValues::from_stats_opt(stats)
             }
         }
     }
@@ -345,17 +358,23 @@ impl ReadFormat {
         &self,
         row_groups: &[impl Borrow<RowGroupMetaData>],
         column_id: ColumnId,
-    ) -> Option<ArrayRef> {
-        let column = self.metadata.column_by_id(column_id)?;
+    ) -> StatValues {
+        let Some(column) = self.metadata.column_by_id(column_id) else {
+            // No such column in the SST.
+            return StatValues::NoColumn;
+        };
         match column.semantic_type {
-            SemanticType::Tag => None,
+            SemanticType::Tag => StatValues::NoStats,
             SemanticType::Field => {
-                let index = self.field_id_to_index.get(&column_id)?;
-                Self::column_null_counts(row_groups, *index)
+                // Safety: `field_id_to_index` is initialized by the semantic type.
+                let index = self.field_id_to_index.get(&column_id).unwrap();
+                let stats = Self::column_null_counts(row_groups, *index);
+                StatValues::from_stats_opt(stats)
             }
             SemanticType::Timestamp => {
                 let index = self.time_index_position();
-                Self::column_null_counts(row_groups, index)
+                let stats = Self::column_null_counts(row_groups, index);
+                StatValues::from_stats_opt(stats)
             }
         }
     }
@@ -390,8 +409,7 @@ impl ReadFormat {
         row_groups: &[impl Borrow<RowGroupMetaData>],
         column: &ColumnMetadata,
         is_min: bool,
-    ) -> Option<ArrayRef> {
-        let primary_key_encoding = self.metadata.primary_key_encoding;
+    ) -> StatValues {
         let is_first_tag = self
             .metadata
             .primary_key
@@ -400,9 +418,28 @@ impl ReadFormat {
             .unwrap_or(false);
         if !is_first_tag {
             // Only the min-max of the first tag is available in the primary key.
-            return None;
+            return StatValues::NoStats;
         }
 
+        StatValues::from_stats_opt(self.first_tag_values(row_groups, column, is_min))
+    }
+
+    /// Returns min/max values of the first tag.
+    /// Returns None if the tag does not have statistics.
+    fn first_tag_values(
+        &self,
+        row_groups: &[impl Borrow<RowGroupMetaData>],
+        column: &ColumnMetadata,
+        is_min: bool,
+    ) -> Option<ArrayRef> {
+        debug_assert!(self
+            .metadata
+            .primary_key
+            .first()
+            .map(|id| *id == column.column_id)
+            .unwrap_or(false));
+
+        let primary_key_encoding = self.metadata.primary_key_encoding;
         let converter = build_primary_key_codec_with_fields(
             primary_key_encoding,
             [(
@@ -452,6 +489,7 @@ impl ReadFormat {
     }
 
     /// Returns min/max values of specific non-tag columns.
+    /// Returns None if the column does not have statistics.
     fn column_values(
         row_groups: &[impl Borrow<RowGroupMetaData>],
         column: &ColumnMetadata,
@@ -544,6 +582,29 @@ impl ReadFormat {
     }
 }
 
+/// Values of column statistics of the SST.
+///
+/// It also distinguishes the case that a column is not found and
+/// the column exists but has no statistics.
+pub enum StatValues {
+    /// Values of each row group.
+    Values(ArrayRef),
+    /// No such column.
+    NoColumn,
+    /// Column exists but has no statistics.
+    NoStats,
+}
+
+impl StatValues {
+    /// Creates a new `StatValues` instance from optional statistics.
+    pub fn from_stats_opt(stats: Option<ArrayRef>) -> Self {
+        match stats {
+            Some(stats) => StatValues::Values(stats),
+            None => StatValues::NoStats,
+        }
+    }
+}
+
 #[cfg(test)]
 impl ReadFormat {
     /// Creates a helper with existing `metadata` and all columns.

src/mito2/src/sst/parquet/stats.rs

@@ -25,7 +25,7 @@ use parquet::file::metadata::RowGroupMetaData;
 use store_api::metadata::RegionMetadataRef;
 use store_api::storage::ColumnId;
 
-use crate::sst::parquet::format::ReadFormat;
+use crate::sst::parquet::format::{ReadFormat, StatValues};
 
 /// Statistics for pruning row groups.
 pub(crate) struct RowGroupPruningStats<'a, T> {
@@ -100,16 +100,18 @@ impl<T: Borrow<RowGroupMetaData>> PruningStatistics for RowGroupPruningStats<'_,
     fn min_values(&self, column: &Column) -> Option<ArrayRef> {
         let column_id = self.column_id_to_prune(&column.name)?;
         match self.read_format.min_values(self.row_groups, column_id) {
-            Some(values) => Some(values),
-            None => self.compat_default_value(&column.name),
+            StatValues::Values(values) => Some(values),
+            StatValues::NoColumn => self.compat_default_value(&column.name),
+            StatValues::NoStats => None,
         }
     }
 
     fn max_values(&self, column: &Column) -> Option<ArrayRef> {
         let column_id = self.column_id_to_prune(&column.name)?;
         match self.read_format.max_values(self.row_groups, column_id) {
-            Some(values) => Some(values),
-            None => self.compat_default_value(&column.name),
+            StatValues::Values(values) => Some(values),
+            StatValues::NoColumn => self.compat_default_value(&column.name),
+            StatValues::NoStats => None,
         }
     }
 
@@ -118,10 +120,12 @@ impl<T: Borrow<RowGroupMetaData>> PruningStatistics for RowGroupPruningStats<'_,
     }
 
     fn null_counts(&self, column: &Column) -> Option<ArrayRef> {
-        let Some(column_id) = self.column_id_to_prune(&column.name) else {
-            return self.compat_null_count(&column.name);
-        };
-        self.read_format.null_counts(self.row_groups, column_id)
+        let column_id = self.column_id_to_prune(&column.name)?;
+        match self.read_format.null_counts(self.row_groups, column_id) {
+            StatValues::Values(values) => Some(values),
+            StatValues::NoColumn => self.compat_null_count(&column.name),
+            StatValues::NoStats => None,
+        }
     }
 
     fn row_counts(&self, _column: &Column) -> Option<ArrayRef> {

src/query/src/datafusion/planner.rs

@@ -20,7 +20,7 @@ use arrow_schema::DataType;
 use catalog::table_source::DfTableSourceProvider;
 use common_function::aggr::{
     GeoPathAccumulator, HllState, UddSketchState, GEO_PATH_NAME, HLL_MERGE_NAME, HLL_NAME,
-    UDDSKETCH_STATE_NAME,
+    UDDSKETCH_MERGE_NAME, UDDSKETCH_STATE_NAME,
 };
 use common_function::scalars::udf::create_udf;
 use common_query::logical_plan::create_aggregate_function;
@@ -165,7 +165,9 @@ impl ContextProvider for DfContextProviderAdapter {
 
     fn get_aggregate_meta(&self, name: &str) -> Option<Arc<AggregateUDF>> {
         if name == UDDSKETCH_STATE_NAME {
-            return Some(Arc::new(UddSketchState::udf_impl()));
+            return Some(Arc::new(UddSketchState::state_udf_impl()));
+        } else if name == UDDSKETCH_MERGE_NAME {
+            return Some(Arc::new(UddSketchState::merge_udf_impl()));
         } else if name == HLL_NAME {
             return Some(Arc::new(HllState::state_udf_impl()));
         } else if name == HLL_MERGE_NAME {

src/query/src/query_engine/default_serializer.rs

@@ -128,7 +128,8 @@ impl SubstraitPlanDecoder for DefaultPlanDecoder {
             session_state
                 .register_udf(udf)
                 .context(RegisterUdfSnafu { name: func.name() })?;
-            let _ = session_state.register_udaf(Arc::new(UddSketchState::udf_impl()));
+            let _ = session_state.register_udaf(Arc::new(UddSketchState::state_udf_impl()));
+            let _ = session_state.register_udaf(Arc::new(UddSketchState::merge_udf_impl()));
             let _ = session_state.register_udaf(Arc::new(HllState::state_udf_impl()));
             let _ = session_state.register_udaf(Arc::new(HllState::merge_udf_impl()));
             let _ = session_state.register_udaf(Arc::new(GeoPathAccumulator::udf_impl()));

tests/cases/standalone/common/aggregate/uddsketch.result

@@ -52,7 +52,41 @@ select uddsketch_calc(0.95, uddsketch_state(128, 0.01, `value`)) from test_uddsk
 | 100.49456770856492                                                                           |
 +----------------------------------------------------------------------------------------------+
 
+CREATE TABLE grouped_uddsketch (
+    `state` BINARY,
+    id_group INT PRIMARY KEY,
+    `ts` timestamp time index default now()
+);
+
+Affected Rows: 0
+
+INSERT INTO grouped_uddsketch (`state`, id_group) SELECT uddsketch_state(128, 0.01, `value`), `id`/5*5 as id_group FROM test_uddsketch GROUP BY id_group;
+
+Affected Rows: 3
+
+SELECT uddsketch_calc(0.1, uddsketch_merge(128, 0.01, `state`)) FROM grouped_uddsketch;
+
++------------------------------------------------------------------------------------------------+
+| uddsketch_calc(Float64(0.1),uddsketch_merge(Int64(128),Float64(0.01),grouped_uddsketch.state)) |
++------------------------------------------------------------------------------------------------+
+| 19.886670240866184                                                                             |
++------------------------------------------------------------------------------------------------+
+
+-- should fail
+SELECT uddsketch_calc(0.1, uddsketch_merge(128, 0.1, `state`)) FROM grouped_uddsketch;
+
+Error: 3001(EngineExecuteQuery), Error during planning: Merging UDDSketch with different parameters: arguments=(128, 0.1) vs actual input=(128, 0.01)
+
+-- should fail
+SELECT uddsketch_calc(0.1, uddsketch_merge(64, 0.01, `state`)) FROM grouped_uddsketch;
+
+Error: 3001(EngineExecuteQuery), Error during planning: Merging UDDSketch with different parameters: arguments=(64, 0.01) vs actual input=(128, 0.01)
+
 drop table test_uddsketch;
 
 Affected Rows: 0
 
+drop table grouped_uddsketch;
+
+Affected Rows: 0
+

tests/cases/standalone/common/aggregate/uddsketch.sql

@@ -24,4 +24,21 @@ select uddsketch_calc(0.75, uddsketch_state(128, 0.01, `value`)) from test_uddsk
 
 select uddsketch_calc(0.95, uddsketch_state(128, 0.01, `value`)) from test_uddsketch;
 
+CREATE TABLE grouped_uddsketch (
+    `state` BINARY,
+    id_group INT PRIMARY KEY,
+    `ts` timestamp time index default now()
+);
+
+INSERT INTO grouped_uddsketch (`state`, id_group) SELECT uddsketch_state(128, 0.01, `value`), `id`/5*5 as id_group FROM test_uddsketch GROUP BY id_group;
+
+SELECT uddsketch_calc(0.1, uddsketch_merge(128, 0.01, `state`)) FROM grouped_uddsketch;
+
+-- should fail
+SELECT uddsketch_calc(0.1, uddsketch_merge(128, 0.1, `state`)) FROM grouped_uddsketch;
+
+-- should fail
+SELECT uddsketch_calc(0.1, uddsketch_merge(64, 0.01, `state`)) FROM grouped_uddsketch;
+
 drop table test_uddsketch;
+drop table grouped_uddsketch;

tests/cases/standalone/common/flow/flow_advance_ttl.result

@@ -31,6 +31,15 @@ FROM
 Affected Rows: 0
 
 -- SQLNESS ARG restart=true
+SELECT 1;
+
++----------+
+| Int64(1) |
++----------+
+| 1        |
++----------+
+
+-- SQLNESS SLEEP 3s
 INSERT INTO
     distinct_basic
 VALUES

tests/cases/standalone/common/flow/flow_advance_ttl.sql

@@ -23,6 +23,9 @@ FROM
     distinct_basic;
 
 -- SQLNESS ARG restart=true
+SELECT 1;
+
+-- SQLNESS SLEEP 3s
 INSERT INTO
     distinct_basic
 VALUES

tests/cases/standalone/common/flow/flow_auto_sink_table.result

@@ -44,6 +44,15 @@ ADMIN FLUSH_FLOW('test_numbers_basic');
 +----------------------------------------+
 
 -- SQLNESS ARG restart=true
+SELECT 1;
+
++----------+
+| Int64(1) |
++----------+
+| 1        |
++----------+
+
+-- SQLNESS SLEEP 3s
 SHOW CREATE TABLE out_num_cnt_basic;
 
 +-------------------+--------------------------------------------------+
@@ -101,6 +110,16 @@ GROUP BY
 
 Affected Rows: 0
 
+-- SQLNESS ARG restart=true
+SELECT 1;
+
++----------+
+| Int64(1) |
++----------+
+| 1        |
++----------+
+
+-- SQLNESS SLEEP 3s
 SHOW CREATE TABLE out_num_cnt_basic;
 
 +-------------------+--------------------------------------------------+
@@ -118,6 +137,15 @@ SHOW CREATE TABLE out_num_cnt_basic;
 +-------------------+--------------------------------------------------+
 
 -- SQLNESS ARG restart=true
+SELECT 1;
+
++----------+
+| Int64(1) |
++----------+
+| 1        |
++----------+
+
+-- SQLNESS SLEEP 3s
 SHOW CREATE FLOW test_numbers_basic;
 
 +--------------------+---------------------------------------------------------------------------------------+

tests/cases/standalone/common/flow/flow_auto_sink_table.sql

@@ -20,6 +20,9 @@ SHOW CREATE TABLE out_num_cnt_basic;
 ADMIN FLUSH_FLOW('test_numbers_basic');
 
 -- SQLNESS ARG restart=true
+SELECT 1;
+
+-- SQLNESS SLEEP 3s
 SHOW CREATE TABLE out_num_cnt_basic;
 
 SHOW CREATE FLOW test_numbers_basic;
@@ -44,10 +47,16 @@ FROM
     numbers_input_basic
 GROUP BY
     ts;
+-- SQLNESS ARG restart=true
+SELECT 1;
 
+-- SQLNESS SLEEP 3s
 SHOW CREATE TABLE out_num_cnt_basic;
 
 -- SQLNESS ARG restart=true
+SELECT 1;
+
+-- SQLNESS SLEEP 3s
 SHOW CREATE FLOW test_numbers_basic;
 
 SHOW CREATE TABLE out_num_cnt_basic;

tests/cases/standalone/common/flow/flow_basic.result

@@ -62,6 +62,15 @@ SHOW CREATE TABLE out_num_cnt_basic;
 +-------------------+--------------------------------------------------+
 
 -- SQLNESS ARG restart=true
+SELECT 1;
+
++----------+
+| Int64(1) |
++----------+
+| 1        |
++----------+
+
+-- SQLNESS SLEEP 3s
 INSERT INTO
     numbers_input_basic
 VALUES
@@ -206,6 +215,15 @@ SHOW CREATE TABLE out_basic;
 +-----------+---------------------------------------------+
 
 -- SQLNESS ARG restart=true
+SELECT 1;
+
++----------+
+| Int64(1) |
++----------+
+| 1        |
++----------+
+
+-- SQLNESS SLEEP 3s
 INSERT INTO
     input_basic
 VALUES
@@ -306,6 +324,15 @@ ADMIN FLUSH_FLOW('test_distinct_basic');
 +-----------------------------------------+
 
 -- SQLNESS ARG restart=true
+SELECT 1;
+
++----------+
+| Int64(1) |
++----------+
+| 1        |
++----------+
+
+-- SQLNESS SLEEP 3s
 INSERT INTO
     distinct_basic
 VALUES
@@ -1665,6 +1692,15 @@ ADMIN FLUSH_FLOW('test_numbers_basic');
 +----------------------------------------+
 
 -- SQLNESS ARG restart=true
+SELECT 1;
+
++----------+
+| Int64(1) |
++----------+
+| 1        |
++----------+
+
+-- SQLNESS SLEEP 3s
 INSERT INTO
     numbers_input_basic
 VALUES

tests/cases/standalone/common/flow/flow_basic.sql

@@ -24,6 +24,9 @@ ADMIN FLUSH_FLOW('test_numbers_basic');
 SHOW CREATE TABLE out_num_cnt_basic;
 
 -- SQLNESS ARG restart=true
+SELECT 1;
+
+-- SQLNESS SLEEP 3s
 INSERT INTO
     numbers_input_basic
 VALUES
@@ -91,6 +94,9 @@ FROM
 SHOW CREATE TABLE out_basic;
 
 -- SQLNESS ARG restart=true
+SELECT 1;
+
+-- SQLNESS SLEEP 3s
 INSERT INTO
     input_basic
 VALUES
@@ -130,6 +136,9 @@ SHOW CREATE TABLE out_distinct_basic;
 ADMIN FLUSH_FLOW('test_distinct_basic');
 
 -- SQLNESS ARG restart=true
+SELECT 1;
+
+-- SQLNESS SLEEP 3s
 INSERT INTO
     distinct_basic
 VALUES
@@ -788,6 +797,9 @@ SHOW CREATE TABLE out_num_cnt_basic;
 ADMIN FLUSH_FLOW('test_numbers_basic');
 
 -- SQLNESS ARG restart=true
+SELECT 1;
+
+-- SQLNESS SLEEP 3s
 INSERT INTO
     numbers_input_basic
 VALUES

tests/cases/standalone/common/flow/flow_rebuild.result

@@ -730,10 +730,21 @@ SELECT key FROM api_stats;
 +-----+
 
 -- SQLNESS ARG restart=true
+SELECT 1;
+
++----------+
+| Int64(1) |
++----------+
+| 1        |
++----------+
+
+-- SQLNESS SLEEP 5s
 INSERT INTO `api_log` (`time`, `key`, `status_code`, `method`, `path`, `raw_query`, `user_agent`, `client_ip`, `duration`, `count`) VALUES (now(), '2', 0, 'GET', '/lightning/v1/query', 'key=1&since=600', 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36', '1', 21, 1);
 
 Affected Rows: 1
 
+-- wait more time so flownode have time to recover flows
+-- SQLNESS SLEEP 5s
 -- SQLNESS REPLACE (ADMIN\sFLUSH_FLOW\('\w+'\)\s+\|\n\+-+\+\n\|\s+)[0-9]+\s+\| $1 FLOW_FLUSHED  |
 ADMIN FLUSH_FLOW('api_stats_flow');
 

tests/cases/standalone/common/flow/flow_rebuild.sql

@@ -399,8 +399,13 @@ ADMIN FLUSH_FLOW('api_stats_flow');
 SELECT key FROM api_stats;
 
 -- SQLNESS ARG restart=true
+SELECT 1;
+
+-- SQLNESS SLEEP 5s
 INSERT INTO `api_log` (`time`, `key`, `status_code`, `method`, `path`, `raw_query`, `user_agent`, `client_ip`, `duration`, `count`) VALUES (now(), '2', 0, 'GET', '/lightning/v1/query', 'key=1&since=600', 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36', '1', 21, 1);
 
+-- wait more time so flownode have time to recover flows
+-- SQLNESS SLEEP 5s
 -- SQLNESS REPLACE (ADMIN\sFLUSH_FLOW\('\w+'\)\s+\|\n\+-+\+\n\|\s+)[0-9]+\s+\| $1 FLOW_FLUSHED  |
 ADMIN FLUSH_FLOW('api_stats_flow');
 

tests/cases/standalone/common/flow/flow_step_aggr.result

@@ -50,6 +50,7 @@ ADMIN FLUSH_FLOW('calc_access_log_10s');
 +-----------------------------------------+
 
 -- query should return 3 rows
+-- SQLNESS SORT_RESULT 3 1
 SELECT "url", time_window FROM access_log_10s
 ORDER BY
     time_window;
@@ -63,6 +64,7 @@ ORDER BY
 +------------+---------------------+
 
 -- use hll_count to query the approximate data in access_log_10s
+-- SQLNESS SORT_RESULT 3 1
 SELECT "url", time_window, hll_count(state) FROM access_log_10s
 ORDER BY
     time_window;
@@ -76,6 +78,7 @@ ORDER BY
 +------------+---------------------+---------------------------------+
 
 -- further, we can aggregate 10 seconds of data to every minute, by using hll_merge to merge 10 seconds of hyperloglog state
+-- SQLNESS SORT_RESULT 3 1
 SELECT
     "url",
     date_bin('1 minute'::INTERVAL, time_window) AS time_window_1m,
@@ -91,8 +94,8 @@ ORDER BY
 +------------+---------------------+------------+
 | url        | time_window_1m      | uv_per_min |
 +------------+---------------------+------------+
-| /not_found | 2025-03-04T00:00:00 | 1          |
 | /dashboard | 2025-03-04T00:00:00 | 3          |
+| /not_found | 2025-03-04T00:00:00 | 1          |
 +------------+---------------------+------------+
 
 DROP FLOW calc_access_log_10s;
@@ -201,6 +204,13 @@ CREATE TABLE percentile_5s (
 
 Affected Rows: 0
 
+CREATE TABLE percentile_10s (
+    "percentile_state" BINARY,
+    time_window timestamp(0) time index
+);
+
+Affected Rows: 0
+
 CREATE FLOW calc_percentile_5s SINK TO percentile_5s
 AS
 SELECT
@@ -213,6 +223,18 @@ GROUP BY
 
 Affected Rows: 0
 
+CREATE FLOW calc_percentile_10s SINK TO percentile_10s
+AS
+SELECT
+    uddsketch_merge(128, 0.01, percentile_state),
+    date_bin('10 seconds'::INTERVAL, time_window) AS time_window
+FROM
+    percentile_5s
+GROUP BY
+    date_bin('10 seconds'::INTERVAL, time_window);
+
+Affected Rows: 0
+
 INSERT INTO percentile_base ("id", "value", ts) VALUES
     (1, 10.0, 1),
     (2, 20.0, 2),
@@ -236,6 +258,15 @@ ADMIN FLUSH_FLOW('calc_percentile_5s');
 |  FLOW_FLUSHED  |
 +----------------------------------------+
 
+-- SQLNESS REPLACE (ADMIN\sFLUSH_FLOW\('\w+'\)\s+\|\n\+-+\+\n\|\s+)[0-9]+\s+\| $1 FLOW_FLUSHED  |
+ADMIN FLUSH_FLOW('calc_percentile_10s');
+
++-----------------------------------------+
+| ADMIN FLUSH_FLOW('calc_percentile_10s') |
++-----------------------------------------+
+|  FLOW_FLUSHED  |
++-----------------------------------------+
+
 SELECT
     time_window,
     uddsketch_calc(0.99, percentile_state) AS p99
@@ -252,14 +283,37 @@ ORDER BY
 | 1970-01-01T00:00:10 |                    |
 +---------------------+--------------------+
 
+SELECT
+    time_window,
+    uddsketch_calc(0.99, percentile_state) AS p99
+FROM
+    percentile_10s
+ORDER BY
+    time_window;
+
++---------------------+--------------------+
+| time_window         | p99                |
++---------------------+--------------------+
+| 1970-01-01T00:00:00 | 59.745049810145126 |
+| 1970-01-01T00:00:10 |                    |
++---------------------+--------------------+
+
 DROP FLOW calc_percentile_5s;
 
 Affected Rows: 0
 
+DROP FLOW calc_percentile_10s;
+
+Affected Rows: 0
+
 DROP TABLE percentile_5s;
 
 Affected Rows: 0
 
+DROP TABLE percentile_10s;
+
+Affected Rows: 0
+
 DROP TABLE percentile_base;
 
 Affected Rows: 0

tests/cases/standalone/common/flow/flow_step_aggr.sql

@@ -36,16 +36,19 @@ INSERT INTO access_log VALUES
 ADMIN FLUSH_FLOW('calc_access_log_10s');
 
 -- query should return 3 rows
+-- SQLNESS SORT_RESULT 3 1
 SELECT "url", time_window FROM access_log_10s
 ORDER BY
     time_window;
 
 -- use hll_count to query the approximate data in access_log_10s
+-- SQLNESS SORT_RESULT 3 1
 SELECT "url", time_window, hll_count(state) FROM access_log_10s
 ORDER BY
     time_window;
 
 -- further, we can aggregate 10 seconds of data to every minute, by using hll_merge to merge 10 seconds of hyperloglog state
+-- SQLNESS SORT_RESULT 3 1
 SELECT
     "url",
     date_bin('1 minute'::INTERVAL, time_window) AS time_window_1m,
@@ -123,6 +126,11 @@ CREATE TABLE percentile_5s (
     time_window timestamp(0) time index
 );
 
+CREATE TABLE percentile_10s (
+    "percentile_state" BINARY,
+    time_window timestamp(0) time index
+);
+
 CREATE FLOW calc_percentile_5s SINK TO percentile_5s
 AS
 SELECT
@@ -133,6 +141,16 @@ FROM
 GROUP BY
     time_window;
 
+CREATE FLOW calc_percentile_10s SINK TO percentile_10s
+AS
+SELECT
+    uddsketch_merge(128, 0.01, percentile_state),
+    date_bin('10 seconds'::INTERVAL, time_window) AS time_window
+FROM
+    percentile_5s
+GROUP BY
+    date_bin('10 seconds'::INTERVAL, time_window);
+
 INSERT INTO percentile_base ("id", "value", ts) VALUES
     (1, 10.0, 1),
     (2, 20.0, 2),
@@ -148,6 +166,9 @@ INSERT INTO percentile_base ("id", "value", ts) VALUES
 -- SQLNESS REPLACE (ADMIN\sFLUSH_FLOW\('\w+'\)\s+\|\n\+-+\+\n\|\s+)[0-9]+\s+\| $1 FLOW_FLUSHED  |
 ADMIN FLUSH_FLOW('calc_percentile_5s');
 
+-- SQLNESS REPLACE (ADMIN\sFLUSH_FLOW\('\w+'\)\s+\|\n\+-+\+\n\|\s+)[0-9]+\s+\| $1 FLOW_FLUSHED  |
+ADMIN FLUSH_FLOW('calc_percentile_10s');
+
 SELECT
     time_window,
     uddsketch_calc(0.99, percentile_state) AS p99
@@ -156,6 +177,16 @@ FROM
 ORDER BY
     time_window;
 
+SELECT
+    time_window,
+    uddsketch_calc(0.99, percentile_state) AS p99
+FROM
+    percentile_10s
+ORDER BY
+    time_window;
+
 DROP FLOW calc_percentile_5s;
+DROP FLOW calc_percentile_10s;
 DROP TABLE percentile_5s;
+DROP TABLE percentile_10s;
 DROP TABLE percentile_base;

tests/cases/standalone/common/flow/show_create_flow.result

@@ -263,6 +263,15 @@ SELECT flow_name, table_catalog, flow_definition, source_table_names FROM INFORM
 
 -- makesure after recover should be the same
 -- SQLNESS ARG restart=true
+SELECT 1;
+
++----------+
+| Int64(1) |
++----------+
+| 1        |
++----------+
+
+-- SQLNESS SLEEP 3s
 SELECT flow_name, table_catalog, flow_definition, source_table_names FROM INFORMATION_SCHEMA.FLOWS WHERE flow_name='filter_numbers_show';
 
 +---------------------+---------------+-------------------------------------------------------------+------------------------------------+

tests/cases/standalone/common/flow/show_create_flow.sql

@@ -108,6 +108,9 @@ SELECT flow_name, table_catalog, flow_definition, source_table_names FROM INFORM
 
 -- makesure after recover should be the same
 -- SQLNESS ARG restart=true
+SELECT 1;
+
+-- SQLNESS SLEEP 3s
 
 SELECT flow_name, table_catalog, flow_definition, source_table_names FROM INFORMATION_SCHEMA.FLOWS WHERE flow_name='filter_numbers_show';
 

tests/cases/standalone/common/function/time.result

@@ -9,7 +9,7 @@ select GREATEST('1999-01-30', '2023-03-01');
 +-------------------------------------------------+
 | greatest(Utf8("1999-01-30"),Utf8("2023-03-01")) |
 +-------------------------------------------------+
-| 2023-03-01T00:00:00                             |
+| 2023-03-01                                      |
 +-------------------------------------------------+
 
 select GREATEST('2000-02-11'::Date, '2020-12-30'::Date);

tests/cases/standalone/common/select/prune_pk.result

@@ -0,0 +1,158 @@
+CREATE TABLE IF NOT EXISTS `test_multi_pk_filter` ( `namespace` STRING NULL, `env` STRING NULL DEFAULT 'NULL', `flag` INT NULL, `total` BIGINT NULL, `greptime_timestamp` TIMESTAMP(9) NOT NULL, TIME INDEX (`greptime_timestamp`), PRIMARY KEY (`namespace`, `env`, `flag`) ) ENGINE=mito;
+
+Affected Rows: 0
+
+INSERT INTO test_multi_pk_filter
+    (namespace, env, flag, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'production', 1, 5289, '2023-05-15 10:00:00');
+
+Affected Rows: 1
+
+INSERT INTO test_multi_pk_filter
+    (namespace, env, flag, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'production', 0, 421, '2023-05-15 10:05:00');
+
+Affected Rows: 1
+
+INSERT INTO test_multi_pk_filter
+    (namespace, env, flag, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'dev', 1, 356, '2023-05-15 10:10:00');
+
+Affected Rows: 1
+
+ADMIN FLUSH_TABLE('test_multi_pk_filter');
+
++-------------------------------------------+
+| ADMIN FLUSH_TABLE('test_multi_pk_filter') |
++-------------------------------------------+
+| 0                                         |
++-------------------------------------------+
+
+INSERT INTO test_multi_pk_filter
+    (namespace, env, flag, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'dev', 1, 412, '2023-05-15 10:15:00');
+
+Affected Rows: 1
+
+INSERT INTO test_multi_pk_filter
+    (namespace, env, flag, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'dev', 1, 298, '2023-05-15 10:20:00');
+
+Affected Rows: 1
+
+INSERT INTO test_multi_pk_filter
+    (namespace, env, flag, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'production', 1, 5289, '2023-05-15 10:25:00');
+
+Affected Rows: 1
+
+INSERT INTO test_multi_pk_filter
+    (namespace, env, flag, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'production', 1, 5874, '2023-05-15 10:30:00');
+
+Affected Rows: 1
+
+ADMIN FLUSH_TABLE('test_multi_pk_filter');
+
++-------------------------------------------+
+| ADMIN FLUSH_TABLE('test_multi_pk_filter') |
++-------------------------------------------+
+| 0                                         |
++-------------------------------------------+
+
+INSERT INTO test_multi_pk_filter
+    (namespace, env, flag, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'production', 1, 6132, '2023-05-15 10:35:00');
+
+Affected Rows: 1
+
+INSERT INTO test_multi_pk_filter
+    (namespace, env, flag, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'testing', 1, 1287, '2023-05-15 10:40:00');
+
+Affected Rows: 1
+
+INSERT INTO test_multi_pk_filter
+    (namespace, env, flag, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'testing', 1, 1432, '2023-05-15 10:45:00');
+
+Affected Rows: 1
+
+INSERT INTO test_multi_pk_filter
+    (namespace, env, flag, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'testing', 1, 1056, '2023-05-15 10:50:00');
+
+Affected Rows: 1
+
+SELECT greptime_timestamp, namespace, env, total FROM test_multi_pk_filter WHERE
+    greptime_timestamp BETWEEN '2023-05-15 10:00:00' AND '2023-05-15 11:00:00' AND flag = 1 AND namespace = 'thermostat_v2'
+    ORDER BY greptime_timestamp;
+
++---------------------+---------------+------------+-------+
+| greptime_timestamp  | namespace     | env        | total |
++---------------------+---------------+------------+-------+
+| 2023-05-15T10:00:00 | thermostat_v2 | production | 5289  |
+| 2023-05-15T10:10:00 | thermostat_v2 | dev        | 356   |
+| 2023-05-15T10:15:00 | thermostat_v2 | dev        | 412   |
+| 2023-05-15T10:20:00 | thermostat_v2 | dev        | 298   |
+| 2023-05-15T10:25:00 | thermostat_v2 | production | 5289  |
+| 2023-05-15T10:30:00 | thermostat_v2 | production | 5874  |
+| 2023-05-15T10:35:00 | thermostat_v2 | production | 6132  |
+| 2023-05-15T10:40:00 | thermostat_v2 | testing    | 1287  |
+| 2023-05-15T10:45:00 | thermostat_v2 | testing    | 1432  |
+| 2023-05-15T10:50:00 | thermostat_v2 | testing    | 1056  |
++---------------------+---------------+------------+-------+
+
+SELECT greptime_timestamp, namespace, env, total FROM test_multi_pk_filter WHERE
+    greptime_timestamp BETWEEN '2023-05-15 10:00:00' AND '2023-05-15 11:00:00' AND flag = 1 AND namespace = 'thermostat_v2' AND env='dev'
+    ORDER BY greptime_timestamp;
+
++---------------------+---------------+-----+-------+
+| greptime_timestamp  | namespace     | env | total |
++---------------------+---------------+-----+-------+
+| 2023-05-15T10:10:00 | thermostat_v2 | dev | 356   |
+| 2023-05-15T10:15:00 | thermostat_v2 | dev | 412   |
+| 2023-05-15T10:20:00 | thermostat_v2 | dev | 298   |
++---------------------+---------------+-----+-------+
+
+DROP TABLE test_multi_pk_filter;
+
+Affected Rows: 0
+
+CREATE TABLE IF NOT EXISTS `test_multi_pk_null` ( `namespace` STRING NULL, `env` STRING NULL DEFAULT 'NULL', `total` BIGINT NULL, `greptime_timestamp` TIMESTAMP(9) NOT NULL, TIME INDEX (`greptime_timestamp`), PRIMARY KEY (`namespace`, `env`) ) ENGINE=mito;
+
+Affected Rows: 0
+
+INSERT INTO test_multi_pk_null
+    (namespace, env, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'production', 5289, '2023-05-15 10:00:00');
+
+Affected Rows: 1
+
+INSERT INTO test_multi_pk_null
+    (namespace, env, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'production', 421, '2023-05-15 10:05:00');
+
+Affected Rows: 1
+
+ADMIN FLUSH_TABLE('test_multi_pk_null');
+
++-----------------------------------------+
+| ADMIN FLUSH_TABLE('test_multi_pk_null') |
++-----------------------------------------+
+| 0                                       |
++-----------------------------------------+
+
+SELECT * FROM test_multi_pk_null WHERE env IS NOT NULL;
+
++---------------+------------+-------+---------------------+
+| namespace     | env        | total | greptime_timestamp  |
++---------------+------------+-------+---------------------+
+| thermostat_v2 | production | 5289  | 2023-05-15T10:00:00 |
+| thermostat_v2 | production | 421   | 2023-05-15T10:05:00 |
++---------------+------------+-------+---------------------+
+
+DROP TABLE test_multi_pk_null;
+
+Affected Rows: 0
+

tests/cases/standalone/common/select/prune_pk.sql

@@ -0,0 +1,66 @@
+CREATE TABLE IF NOT EXISTS `test_multi_pk_filter` ( `namespace` STRING NULL, `env` STRING NULL DEFAULT 'NULL', `flag` INT NULL, `total` BIGINT NULL, `greptime_timestamp` TIMESTAMP(9) NOT NULL, TIME INDEX (`greptime_timestamp`), PRIMARY KEY (`namespace`, `env`, `flag`) ) ENGINE=mito;
+
+INSERT INTO test_multi_pk_filter
+    (namespace, env, flag, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'production', 1, 5289, '2023-05-15 10:00:00');
+INSERT INTO test_multi_pk_filter
+    (namespace, env, flag, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'production', 0, 421, '2023-05-15 10:05:00');
+INSERT INTO test_multi_pk_filter
+    (namespace, env, flag, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'dev', 1, 356, '2023-05-15 10:10:00');
+
+ADMIN FLUSH_TABLE('test_multi_pk_filter');
+
+INSERT INTO test_multi_pk_filter
+    (namespace, env, flag, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'dev', 1, 412, '2023-05-15 10:15:00');
+INSERT INTO test_multi_pk_filter
+    (namespace, env, flag, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'dev', 1, 298, '2023-05-15 10:20:00');
+INSERT INTO test_multi_pk_filter
+    (namespace, env, flag, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'production', 1, 5289, '2023-05-15 10:25:00');
+INSERT INTO test_multi_pk_filter
+    (namespace, env, flag, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'production', 1, 5874, '2023-05-15 10:30:00');
+
+ADMIN FLUSH_TABLE('test_multi_pk_filter');
+
+INSERT INTO test_multi_pk_filter
+    (namespace, env, flag, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'production', 1, 6132, '2023-05-15 10:35:00');
+INSERT INTO test_multi_pk_filter
+    (namespace, env, flag, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'testing', 1, 1287, '2023-05-15 10:40:00');
+INSERT INTO test_multi_pk_filter
+    (namespace, env, flag, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'testing', 1, 1432, '2023-05-15 10:45:00');
+INSERT INTO test_multi_pk_filter
+    (namespace, env, flag, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'testing', 1, 1056, '2023-05-15 10:50:00');
+
+SELECT greptime_timestamp, namespace, env, total FROM test_multi_pk_filter WHERE
+    greptime_timestamp BETWEEN '2023-05-15 10:00:00' AND '2023-05-15 11:00:00' AND flag = 1 AND namespace = 'thermostat_v2'
+    ORDER BY greptime_timestamp;
+
+SELECT greptime_timestamp, namespace, env, total FROM test_multi_pk_filter WHERE
+    greptime_timestamp BETWEEN '2023-05-15 10:00:00' AND '2023-05-15 11:00:00' AND flag = 1 AND namespace = 'thermostat_v2' AND env='dev'
+    ORDER BY greptime_timestamp;
+
+DROP TABLE test_multi_pk_filter;
+
+CREATE TABLE IF NOT EXISTS `test_multi_pk_null` ( `namespace` STRING NULL, `env` STRING NULL DEFAULT 'NULL', `total` BIGINT NULL, `greptime_timestamp` TIMESTAMP(9) NOT NULL, TIME INDEX (`greptime_timestamp`), PRIMARY KEY (`namespace`, `env`) ) ENGINE=mito;
+
+INSERT INTO test_multi_pk_null
+    (namespace, env, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'production', 5289, '2023-05-15 10:00:00');
+INSERT INTO test_multi_pk_null
+    (namespace, env, total, greptime_timestamp)
+    VALUES ('thermostat_v2', 'production', 421, '2023-05-15 10:05:00');
+
+ADMIN FLUSH_TABLE('test_multi_pk_null');
+
+SELECT * FROM test_multi_pk_null WHERE env IS NOT NULL;
+
+DROP TABLE test_multi_pk_null;