fix: conn pool leak & placeholder feature so ci can compile

chore: even more warning

fix: filter first warn later

Cargo.lock

@@ -4165,6 +4165,7 @@ dependencies = [
  "bytes",
  "cache",
  "catalog",
+ "chrono",
  "client",
  "common-base",
  "common-catalog",

src/client/src/lib.rs

@@ -16,7 +16,6 @@
 
 mod client;
 pub mod client_manager;
-#[cfg(feature = "testing")]
 mod database;
 pub mod error;
 pub mod flow;
@@ -34,7 +33,6 @@ pub use common_recordbatch::{RecordBatches, SendableRecordBatchStream};
 use snafu::OptionExt;
 
 pub use self::client::Client;
-#[cfg(feature = "testing")]
 pub use self::database::Database;
 pub use self::error::{Error, Result};
 use crate::error::{IllegalDatabaseResponseSnafu, ServerSnafu};

src/cmd/src/flownode.rs

@@ -32,7 +32,7 @@ use common_meta::key::TableMetadataManager;
 use common_telemetry::info;
 use common_telemetry::logging::TracingOptions;
 use common_version::{short_version, version};
-use flow::{FlownodeBuilder, FlownodeInstance, FrontendInvoker};
+use flow::{FlownodeBuilder, FlownodeInstance, FrontendClient, FrontendInvoker};
 use meta_client::{MetaClientOptions, MetaClientType};
 use servers::Mode;
 use snafu::{OptionExt, ResultExt};
@@ -317,6 +317,8 @@ impl StartCommand {
             Arc::new(executor),
         );
 
+        let frontend_client = FrontendClient::from_meta_client(meta_client.clone());
+
         let flow_metadata_manager = Arc::new(FlowMetadataManager::new(cached_meta_backend.clone()));
         let flownode_builder = FlownodeBuilder::new(
             opts,
@@ -324,6 +326,7 @@ impl StartCommand {
             table_metadata_manager,
             catalog_manager.clone(),
             flow_metadata_manager,
+            Arc::new(frontend_client),
         )
         .with_heartbeat_task(heartbeat_task);
 

src/cmd/src/standalone.rs

@@ -54,7 +54,10 @@ use datanode::config::{DatanodeOptions, ProcedureConfig, RegionEngineConfig, Sto
 use datanode::datanode::{Datanode, DatanodeBuilder};
 use datanode::region_server::RegionServer;
 use file_engine::config::EngineConfig as FileEngineConfig;
-use flow::{FlowConfig, FlowWorkerManager, FlownodeBuilder, FlownodeOptions, FrontendInvoker};
+use flow::{
+    FlowConfig, FlowWorkerManager, FlownodeBuilder, FlownodeOptions, FrontendClient,
+    FrontendInvoker,
+};
 use frontend::frontend::FrontendOptions;
 use frontend::instance::builder::FrontendBuilder;
 use frontend::instance::{FrontendInstance, Instance as FeInstance, StandaloneDatanodeManager};
@@ -533,12 +536,16 @@ impl StartCommand {
             flow: opts.flow.clone(),
             ..Default::default()
         };
+
+        let fe_server_addr = fe_opts.grpc.bind_addr.clone();
+        let frontend_client = FrontendClient::from_static_grpc_addr(fe_server_addr);
         let flow_builder = FlownodeBuilder::new(
             flownode_options,
             plugins.clone(),
             table_metadata_manager.clone(),
             catalog_manager.clone(),
             flow_metadata_manager.clone(),
+            Arc::new(frontend_client),
         );
         let flownode = Arc::new(
             flow_builder

src/common/grpc/src/channel_manager.rs

@@ -445,10 +445,16 @@ impl Pool {
 
 async fn recycle_channel_in_loop(pool: Arc<Pool>, interval_secs: u64) {
     let mut interval = tokio::time::interval(Duration::from_secs(interval_secs));
-
+    // use weak ref here to prevent pool being leaked
+    let pool_weak = Arc::downgrade(&pool);
     loop {
         let _ = interval.tick().await;
-        pool.retain_channel(|_, c| c.access.swap(0, Ordering::Relaxed) != 0)
+        if let Some(pool) = pool_weak.upgrade() {
+            pool.retain_channel(|_, c| c.access.swap(0, Ordering::Relaxed) != 0)
+        } else {
+            // no one is using this pool, so we can also let go
+            break;
+        }
     }
 }
 

src/common/meta/src/ddl/create_flow.rs

@@ -343,6 +343,7 @@ pub enum FlowType {
 impl FlowType {
     pub const RECORDING_RULE: &str = "recording_rule";
     pub const STREAMING: &str = "streaming";
+    pub const FLOW_TYPE_KEY: &str = "flow_type";
 }
 
 impl Default for FlowType {
@@ -398,7 +399,8 @@ impl From<&CreateFlowData> for CreateRequest {
         };
 
         let flow_type = value.flow_type.unwrap_or_default().to_string();
-        req.flow_options.insert("flow_type".to_string(), flow_type);
+        req.flow_options
+            .insert(FlowType::FLOW_TYPE_KEY.to_string(), flow_type);
         req
     }
 }
@@ -430,7 +432,7 @@ impl From<&CreateFlowData> for (FlowInfoValue, Vec<(FlowPartitionId, FlowRouteVa
             .collect::<Vec<_>>();
 
         let flow_type = value.flow_type.unwrap_or_default().to_string();
-        options.insert("flow_type".to_string(), flow_type);
+        options.insert(FlowType::FLOW_TYPE_KEY.to_string(), flow_type);
 
         let flow_info = FlowInfoValue {
             source_table_ids: value.source_table_ids.clone(),

src/flow/Cargo.toml

@@ -16,6 +16,7 @@ async-trait.workspace = true
 bytes.workspace = true
 cache.workspace = true
 catalog.workspace = true
+chrono.workspace = true
 client.workspace = true
 common-base.workspace = true
 common-config.workspace = true

src/flow/src/adapter.rs

@@ -49,12 +49,13 @@ pub(crate) use crate::adapter::node_context::FlownodeContext;
 use crate::adapter::refill::RefillTask;
 use crate::adapter::table_source::ManagedTableSource;
 use crate::adapter::util::relation_desc_to_column_schemas_with_fallback;
-pub(crate) use crate::adapter::worker::{create_worker, Worker, WorkerHandle};
+pub(crate) use crate::adapter::worker::{create_worker, WorkerHandle};
 use crate::compute::ErrCollector;
 use crate::df_optimizer::sql_to_flow_plan;
 use crate::error::{EvalSnafu, ExternalSnafu, InternalSnafu, InvalidQuerySnafu, UnexpectedSnafu};
 use crate::expr::Batch;
 use crate::metrics::{METRIC_FLOW_INSERT_ELAPSED, METRIC_FLOW_ROWS, METRIC_FLOW_RUN_INTERVAL_MS};
+use crate::recording_rules::RecordingRuleEngine;
 use crate::repr::{self, DiffRow, RelationDesc, Row, BATCH_SIZE};
 
 mod flownode_impl;
@@ -63,7 +64,7 @@ pub(crate) mod refill;
 mod stat;
 #[cfg(test)]
 mod tests;
-mod util;
+pub(crate) mod util;
 mod worker;
 
 pub(crate) mod node_context;
@@ -171,6 +172,8 @@ pub struct FlowWorkerManager {
     flush_lock: RwLock<()>,
     /// receive a oneshot sender to send state size report
     state_report_handler: RwLock<Option<StateReportHandler>>,
+    /// engine for recording rule
+    rule_engine: RecordingRuleEngine,
 }
 
 /// Building FlownodeManager
@@ -185,6 +188,7 @@ impl FlowWorkerManager {
         node_id: Option<u32>,
         query_engine: Arc<dyn QueryEngine>,
         table_meta: TableMetadataManagerRef,
+        rule_engine: RecordingRuleEngine,
     ) -> Self {
         let srv_map = ManagedTableSource::new(
             table_meta.table_info_manager().clone(),
@@ -207,6 +211,7 @@ impl FlowWorkerManager {
             node_id,
             flush_lock: RwLock::new(()),
             state_report_handler: RwLock::new(None),
+            rule_engine,
         }
     }
 
@@ -215,25 +220,6 @@ impl FlowWorkerManager {
         self
     }
 
-    /// Create a flownode manager with one worker
-    pub fn new_with_workers<'s>(
-        node_id: Option<u32>,
-        query_engine: Arc<dyn QueryEngine>,
-        table_meta: TableMetadataManagerRef,
-        num_workers: usize,
-    ) -> (Self, Vec<Worker<'s>>) {
-        let mut zelf = Self::new(node_id, query_engine, table_meta);
-
-        let workers: Vec<_> = (0..num_workers)
-            .map(|_| {
-                let (handle, worker) = create_worker();
-                zelf.add_worker_handle(handle);
-                worker
-            })
-            .collect();
-        (zelf, workers)
-    }
-
     /// add a worker handler to manager, meaning this corresponding worker is under it's manage
     pub fn add_worker_handle(&mut self, handle: WorkerHandle) {
         self.worker_handles.push(handle);
@@ -751,7 +737,11 @@ pub struct CreateFlowArgs {
 /// Create&Remove flow
 impl FlowWorkerManager {
     /// remove a flow by it's id
+    #[allow(unreachable_code)]
     pub async fn remove_flow(&self, flow_id: FlowId) -> Result<(), Error> {
+        // TODO(discord9): reroute some back to streaming engine later
+        return self.rule_engine.remove_flow(flow_id).await;
+
         for handle in self.worker_handles.iter() {
             if handle.contains_flow(flow_id).await? {
                 handle.remove_flow(flow_id).await?;
@@ -767,8 +757,10 @@ impl FlowWorkerManager {
     /// steps to create task:
     /// 1. parse query into typed plan(and optional parse expire_after expr)
     /// 2. render source/sink with output table id and used input table id
-    #[allow(clippy::too_many_arguments)]
+    #[allow(clippy::too_many_arguments, unreachable_code)]
     pub async fn create_flow(&self, args: CreateFlowArgs) -> Result<Option<FlowId>, Error> {
+        // TODO(discord9): reroute some back to streaming engine later
+        return self.rule_engine.create_flow(args).await;
         let CreateFlowArgs {
             flow_id,
             sink_table_name,

src/flow/src/adapter/flownode_impl.rs

@@ -153,7 +153,13 @@ impl Flownode for FlowWorkerManager {
         }
     }
 
+    #[allow(unreachable_code, unused)]
     async fn handle_inserts(&self, request: InsertRequests) -> Result<FlowResponse> {
+        return self
+            .rule_engine
+            .handle_inserts(request)
+            .await
+            .map_err(to_meta_err(snafu::location!()));
         // using try_read to ensure two things:
         // 1. flush wouldn't happen until inserts before it is inserted
         // 2. inserts happening concurrently with flush wouldn't be block by flush
@@ -206,15 +212,15 @@ impl Flownode for FlowWorkerManager {
                     .collect_vec();
                 let table_col_names = table_schema.relation_desc.names;
                 let table_col_names = table_col_names
-                    .iter().enumerate()
-                    .map(|(idx,name)| match name {
-                        Some(name) => Ok(name.clone()),
-                        None => InternalSnafu {
-                            reason: format!("Expect column {idx} of table id={table_id} to have name in table schema, found None"),
-                        }
-                        .fail().map_err(BoxedError::new).context(ExternalSnafu),
-                    })
-                    .collect::<Result<Vec<_>>>()?;
+                        .iter().enumerate()
+                        .map(|(idx,name)| match name {
+                            Some(name) => Ok(name.clone()),
+                            None => InternalSnafu {
+                                reason: format!("Expect column {idx} of table id={table_id} to have name in table schema, found None"),
+                            }
+                            .fail().map_err(BoxedError::new).context(ExternalSnafu),
+                        })
+                        .collect::<Result<Vec<_>>>()?;
                 let name_to_col = HashMap::<_, _>::from_iter(
                     insert_schema
                         .iter()

src/flow/src/adapter/util.rs

@@ -12,6 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+//! Some utility functions
+
 use std::sync::Arc;
 
 use api::helper::ColumnDataTypeWrapper;

src/flow/src/error.rs

@@ -16,6 +16,7 @@
 
 use std::any::Any;
 
+use arrow_schema::ArrowError;
 use common_error::ext::BoxedError;
 use common_error::{define_into_tonic_status, from_err_code_msg_to_header};
 use common_macro::stack_trace_debug;
@@ -53,6 +54,13 @@ pub enum Error {
         location: Location,
     },
 
+    #[snafu(display("Time error"))]
+    Time {
+        source: common_time::error::Error,
+        #[snafu(implicit)]
+        location: Location,
+    },
+
     #[snafu(display("External error"))]
     External {
         source: BoxedError,
@@ -156,6 +164,15 @@ pub enum Error {
         location: Location,
     },
 
+    #[snafu(display("Arrow error: {raw:?} in context: {context}"))]
+    Arrow {
+        #[snafu(source)]
+        raw: ArrowError,
+        context: String,
+        #[snafu(implicit)]
+        location: Location,
+    },
+
     #[snafu(display("Datafusion error: {raw:?} in context: {context}"))]
     Datafusion {
         #[snafu(source)]
@@ -230,6 +247,7 @@ impl ErrorExt for Error {
         match self {
             Self::Eval { .. }
             | Self::JoinTask { .. }
+            | Self::Arrow { .. }
             | Self::Datafusion { .. }
             | Self::InsertIntoFlow { .. } => StatusCode::Internal,
             Self::FlowAlreadyExist { .. } => StatusCode::TableAlreadyExists,
@@ -238,7 +256,9 @@ impl ErrorExt for Error {
             | Self::FlowNotFound { .. }
             | Self::ListFlows { .. } => StatusCode::TableNotFound,
             Self::Plan { .. } | Self::Datatypes { .. } => StatusCode::PlanQuery,
-            Self::InvalidQuery { .. } | Self::CreateFlow { .. } => StatusCode::EngineExecuteQuery,
+            Self::InvalidQuery { .. } | Self::CreateFlow { .. } | Self::Time { .. } => {
+                StatusCode::EngineExecuteQuery
+            }
             Self::Unexpected { .. } => StatusCode::Unexpected,
             Self::NotImplemented { .. } | Self::UnsupportedTemporalFilter { .. } => {
                 StatusCode::Unsupported

src/flow/src/expr/utils.rs

@@ -238,6 +238,7 @@ mod test {
 
         for (sql, current, expected) in &testcases {
             let plan = sql_to_substrait(engine.clone(), sql).await;
+
             let mut ctx = create_test_ctx();
             let flow_plan = TypedPlan::from_substrait_plan(&mut ctx, &plan)
                 .await

src/flow/src/heartbeat.rs

@@ -130,13 +130,6 @@ impl HeartbeatTask {
 
     pub fn shutdown(&self) {
         info!("Close heartbeat task for flownode");
-        if self
-            .running
-            .compare_exchange(true, false, Ordering::AcqRel, Ordering::Acquire)
-            .is_err()
-        {
-            warn!("Call close heartbeat task multiple times");
-        }
     }
 
     fn new_heartbeat_request(

src/flow/src/lib.rs

@@ -33,6 +33,7 @@ mod expr;
 pub mod heartbeat;
 mod metrics;
 mod plan;
+mod recording_rules;
 mod repr;
 mod server;
 mod transform;
@@ -43,4 +44,5 @@ mod test_utils;
 
 pub use adapter::{FlowConfig, FlowWorkerManager, FlowWorkerManagerRef, FlownodeOptions};
 pub use error::{Error, Result};
+pub use recording_rules::FrontendClient;
 pub use server::{FlownodeBuilder, FlownodeInstance, FlownodeServer, FrontendInvoker};

src/flow/src/metrics.rs

@@ -28,6 +28,32 @@ lazy_static! {
         &["table_id"]
     )
     .unwrap();
+    pub static ref METRIC_FLOW_RULE_ENGINE_QUERY_TIME: HistogramVec = register_histogram_vec!(
+        "greptime_flow_rule_engine_query_time",
+        "flow rule engine query time",
+        &["flow_id"],
+        vec![
+            0.0,
+            1.,
+            3.,
+            5.,
+            10.,
+            20.,
+            30.,
+            60.,
+            2. * 60.,
+            5. * 60.,
+            10. * 60.
+        ]
+    )
+    .unwrap();
+    pub static ref METRIC_FLOW_RULE_ENGINE_SLOW_QUERY: HistogramVec = register_histogram_vec!(
+        "greptime_flow_rule_engine_slow_query",
+        "flow rule engine slow query",
+        &["flow_id", "sql", "peer"],
+        vec![60., 2. * 60., 3. * 60., 5. * 60., 10. * 60.]
+    )
+    .unwrap();
     pub static ref METRIC_FLOW_RUN_INTERVAL_MS: IntGauge =
         register_int_gauge!("greptime_flow_run_interval_ms", "flow run interval in ms").unwrap();
     pub static ref METRIC_FLOW_ROWS: IntCounterVec = register_int_counter_vec!(

src/flow/src/recording_rules.rs

@@ -0,0 +1,940 @@
+// 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.
+
+//! Run flow as recording rule which is time-window-aware normal query triggered every tick set by user
+
+mod engine;
+mod frontend_client;
+
+use std::collections::BTreeSet;
+use std::sync::Arc;
+
+use api::helper::pb_value_to_value_ref;
+use catalog::CatalogManagerRef;
+use common_error::ext::BoxedError;
+use common_recordbatch::DfRecordBatch;
+use common_telemetry::warn;
+use common_time::timestamp::TimeUnit;
+use common_time::Timestamp;
+use datafusion::error::Result as DfResult;
+use datafusion::logical_expr::Expr;
+use datafusion::physical_planner::{DefaultPhysicalPlanner, PhysicalPlanner};
+use datafusion::prelude::SessionContext;
+use datafusion::sql::unparser::Unparser;
+use datafusion_common::tree_node::{Transformed, TreeNode, TreeNodeRecursion, TreeNodeRewriter};
+use datafusion_common::{DFSchema, TableReference};
+use datafusion_expr::{ColumnarValue, LogicalPlan};
+use datafusion_physical_expr::PhysicalExprRef;
+use datatypes::prelude::{ConcreteDataType, DataType};
+use datatypes::scalars::ScalarVector;
+use datatypes::schema::TIME_INDEX_KEY;
+use datatypes::value::Value;
+use datatypes::vectors::{
+    TimestampMicrosecondVector, TimestampMillisecondVector, TimestampNanosecondVector,
+    TimestampSecondVector, Vector,
+};
+pub use engine::RecordingRuleEngine;
+pub use frontend_client::FrontendClient;
+use itertools::Itertools;
+use query::parser::QueryLanguageParser;
+use query::QueryEngineRef;
+use session::context::QueryContextRef;
+use snafu::{ensure, OptionExt, ResultExt};
+
+use crate::adapter::util::from_proto_to_data_type;
+use crate::df_optimizer::apply_df_optimizer;
+use crate::error::{ArrowSnafu, DatafusionSnafu, DatatypesSnafu, ExternalSnafu, UnexpectedSnafu};
+use crate::expr::error::DataTypeSnafu;
+use crate::Error;
+
+#[derive(Debug, Clone)]
+pub struct TimeWindowExpr {
+    phy_expr: PhysicalExprRef,
+    column_name: String,
+    logical_expr: Expr,
+    df_schema: DFSchema,
+}
+
+impl TimeWindowExpr {
+    pub fn from_expr(expr: &Expr, column_name: &str, df_schema: &DFSchema) -> Result<Self, Error> {
+        let phy_planner = DefaultPhysicalPlanner::default();
+
+        let phy_expr: PhysicalExprRef = phy_planner
+            .create_physical_expr(expr, df_schema, &SessionContext::new().state())
+            .with_context(|_e| DatafusionSnafu {
+                context: format!(
+                    "Failed to create physical expression from {expr:?} using {df_schema:?}"
+                ),
+            })?;
+        Ok(Self {
+            phy_expr,
+            column_name: column_name.to_string(),
+            logical_expr: expr.clone(),
+            df_schema: df_schema.clone(),
+        })
+    }
+
+    pub fn eval(
+        &self,
+        current: Timestamp,
+    ) -> Result<(Option<Timestamp>, Option<Timestamp>), Error> {
+        let lower_bound =
+            find_expr_time_window_lower_bound(&self.logical_expr, &self.df_schema, current)?;
+        let upper_bound =
+            find_expr_time_window_upper_bound(&self.logical_expr, &self.df_schema, current)?;
+        Ok((lower_bound, upper_bound))
+    }
+
+    /// Find timestamps from rows using time window expr
+    pub async fn handle_rows(
+        &self,
+        rows_list: Vec<api::v1::Rows>,
+    ) -> Result<BTreeSet<Timestamp>, Error> {
+        let mut time_windows = BTreeSet::new();
+
+        for rows in rows_list {
+            // pick the time index column and use it to eval on `self.expr`
+            let ts_col_index = rows
+                .schema
+                .iter()
+                .map(|col| col.column_name.clone())
+                .position(|name| name == self.column_name);
+            let Some(ts_col_index) = ts_col_index else {
+                warn!("can't found time index column in schema: {:?}", rows.schema);
+                continue;
+            };
+            let col_schema = &rows.schema[ts_col_index];
+            let cdt = from_proto_to_data_type(col_schema)?;
+
+            let column_values = rows
+                .rows
+                .iter()
+                .map(|row| &row.values[ts_col_index])
+                .collect_vec();
+
+            let mut vector = cdt.create_mutable_vector(column_values.len());
+            for value in column_values {
+                let value = pb_value_to_value_ref(value, &None);
+                vector.try_push_value_ref(value).context(DataTypeSnafu {
+                    msg: "Failed to convert rows to columns",
+                })?;
+            }
+            let vector = vector.to_vector();
+
+            let df_schema = create_df_schema_for_ts_column(&self.column_name, cdt)?;
+
+            let rb =
+                DfRecordBatch::try_new(df_schema.inner().clone(), vec![vector.to_arrow_array()])
+                    .with_context(|_e| ArrowSnafu {
+                        context: format!(
+                            "Failed to create record batch from {df_schema:?} and {vector:?}"
+                        ),
+                    })?;
+
+            let eval_res = self
+                .phy_expr
+                .evaluate(&rb)
+                .with_context(|_| DatafusionSnafu {
+                    context: format!(
+                        "Failed to evaluate physical expression {:?} on {rb:?}",
+                        self.phy_expr
+                    ),
+                })?;
+
+            let res = columnar_to_ts_vector(&eval_res)?;
+
+            for ts in res.into_iter().flatten() {
+                time_windows.insert(ts);
+            }
+        }
+
+        Ok(time_windows)
+    }
+}
+
+fn create_df_schema_for_ts_column(name: &str, cdt: ConcreteDataType) -> Result<DFSchema, Error> {
+    let arrow_schema = Arc::new(arrow_schema::Schema::new(vec![arrow_schema::Field::new(
+        name,
+        cdt.as_arrow_type(),
+        false,
+    )]));
+
+    let df_schema = DFSchema::from_field_specific_qualified_schema(
+        vec![Some(TableReference::bare("TimeIndexOnlyTable"))],
+        &arrow_schema,
+    )
+    .with_context(|_e| DatafusionSnafu {
+        context: format!("Failed to create DFSchema from arrow schema {arrow_schema:?}"),
+    })?;
+
+    Ok(df_schema)
+}
+
+/// Convert `ColumnarValue` to `Vec<Option<Timestamp>>`
+fn columnar_to_ts_vector(columnar: &ColumnarValue) -> Result<Vec<Option<Timestamp>>, Error> {
+    let val = match columnar {
+        datafusion_expr::ColumnarValue::Array(array) => {
+            let ty = array.data_type();
+            let ty = ConcreteDataType::from_arrow_type(ty);
+            let time_unit = if let ConcreteDataType::Timestamp(ty) = ty {
+                ty.unit()
+            } else {
+                return UnexpectedSnafu {
+                    reason: format!("Non-timestamp type: {ty:?}"),
+                }
+                .fail();
+            };
+
+            match time_unit {
+                TimeUnit::Second => TimestampSecondVector::try_from_arrow_array(array.clone())
+                    .with_context(|_| DatatypesSnafu {
+                        extra: format!("Failed to create vector from arrow array {array:?}"),
+                    })?
+                    .iter_data()
+                    .map(|d| d.map(|d| d.0))
+                    .collect_vec(),
+                TimeUnit::Millisecond => {
+                    TimestampMillisecondVector::try_from_arrow_array(array.clone())
+                        .with_context(|_| DatatypesSnafu {
+                            extra: format!("Failed to create vector from arrow array {array:?}"),
+                        })?
+                        .iter_data()
+                        .map(|d| d.map(|d| d.0))
+                        .collect_vec()
+                }
+                TimeUnit::Microsecond => {
+                    TimestampMicrosecondVector::try_from_arrow_array(array.clone())
+                        .with_context(|_| DatatypesSnafu {
+                            extra: format!("Failed to create vector from arrow array {array:?}"),
+                        })?
+                        .iter_data()
+                        .map(|d| d.map(|d| d.0))
+                        .collect_vec()
+                }
+                TimeUnit::Nanosecond => {
+                    TimestampNanosecondVector::try_from_arrow_array(array.clone())
+                        .with_context(|_| DatatypesSnafu {
+                            extra: format!("Failed to create vector from arrow array {array:?}"),
+                        })?
+                        .iter_data()
+                        .map(|d| d.map(|d| d.0))
+                        .collect_vec()
+                }
+            }
+        }
+        datafusion_expr::ColumnarValue::Scalar(scalar) => {
+            let value = Value::try_from(scalar.clone()).with_context(|_| DatatypesSnafu {
+                extra: format!("Failed to convert scalar {scalar:?} to value"),
+            })?;
+            let ts = value.as_timestamp().context(UnexpectedSnafu {
+                reason: format!("Expect Timestamp, found {:?}", value),
+            })?;
+            vec![Some(ts)]
+        }
+    };
+    Ok(val)
+}
+
+/// Convert sql to datafusion logical plan
+pub async fn sql_to_df_plan(
+    query_ctx: QueryContextRef,
+    engine: QueryEngineRef,
+    sql: &str,
+    optimize: bool,
+) -> Result<LogicalPlan, Error> {
+    let stmt = QueryLanguageParser::parse_sql(sql, &query_ctx)
+        .map_err(BoxedError::new)
+        .context(ExternalSnafu)?;
+    let plan = engine
+        .planner()
+        .plan(&stmt, query_ctx)
+        .await
+        .map_err(BoxedError::new)
+        .context(ExternalSnafu)?;
+    let plan = if optimize {
+        apply_df_optimizer(plan).await?
+    } else {
+        plan
+    };
+    Ok(plan)
+}
+
+/// Return (the column name of time index column, the time window expr, the expected time unit of time index column, the expr's schema for evaluating the time window)
+async fn find_time_window_expr(
+    plan: &LogicalPlan,
+    catalog_man: CatalogManagerRef,
+    query_ctx: QueryContextRef,
+) -> Result<(String, Option<datafusion_expr::Expr>, TimeUnit, DFSchema), Error> {
+    // TODO(discord9): find the expr that do time window
+
+    let mut table_name = None;
+
+    // first find the table source in the logical plan
+    plan.apply(|plan| {
+        let LogicalPlan::TableScan(table_scan) = plan else {
+            return Ok(TreeNodeRecursion::Continue);
+        };
+        table_name = Some(table_scan.table_name.clone());
+        Ok(TreeNodeRecursion::Stop)
+    })
+    .with_context(|_| DatafusionSnafu {
+        context: format!("Can't find table source in plan {plan:?}"),
+    })?;
+    let Some(table_name) = table_name else {
+        UnexpectedSnafu {
+            reason: format!("Can't find table source in plan {plan:?}"),
+        }
+        .fail()?
+    };
+
+    let current_schema = query_ctx.current_schema();
+
+    let catalog_name = table_name.catalog().unwrap_or(query_ctx.current_catalog());
+    let schema_name = table_name.schema().unwrap_or(&current_schema);
+    let table_name = table_name.table();
+
+    let Some(table_ref) = catalog_man
+        .table(catalog_name, schema_name, table_name, Some(&query_ctx))
+        .await
+        .map_err(BoxedError::new)
+        .context(ExternalSnafu)?
+    else {
+        UnexpectedSnafu {
+            reason: format!(
+                "Can't find table {table_name:?} in catalog {catalog_name:?}/{schema_name:?}"
+            ),
+        }
+        .fail()?
+    };
+
+    let schema = &table_ref.table_info().meta.schema;
+
+    let ts_index = schema.timestamp_column().context(UnexpectedSnafu {
+        reason: format!("Can't find timestamp column in table {table_name:?}"),
+    })?;
+
+    let ts_col_name = ts_index.name.clone();
+
+    let expected_time_unit = ts_index.data_type.as_timestamp().with_context(|| UnexpectedSnafu {
+        reason: format!(
+            "Expected timestamp column {ts_col_name:?} in table {table_name:?} to be timestamp, but got {ts_index:?}"
+        ),
+    })?.unit();
+
+    let arrow_schema = Arc::new(arrow_schema::Schema::new(vec![arrow_schema::Field::new(
+        ts_col_name.clone(),
+        ts_index.data_type.as_arrow_type(),
+        false,
+    )]));
+
+    let df_schema = DFSchema::from_field_specific_qualified_schema(
+        vec![Some(TableReference::bare(table_name))],
+        &arrow_schema,
+    )
+    .with_context(|_e| DatafusionSnafu {
+        context: format!("Failed to create DFSchema from arrow schema {arrow_schema:?}"),
+    })?;
+
+    // find the time window expr which refers to the time index column
+    let mut aggr_expr = None;
+    let mut time_window_expr: Option<Expr> = None;
+
+    let find_inner_aggr_expr = |plan: &LogicalPlan| {
+        if let LogicalPlan::Aggregate(aggregate) = plan {
+            aggr_expr = Some(aggregate.clone());
+        };
+
+        Ok(TreeNodeRecursion::Continue)
+    };
+    plan.apply(find_inner_aggr_expr)
+        .with_context(|_| DatafusionSnafu {
+            context: format!("Can't find aggr expr in plan {plan:?}"),
+        })?;
+
+    if let Some(aggregate) = aggr_expr {
+        for group_expr in &aggregate.group_expr {
+            let refs = group_expr.column_refs();
+            if refs.len() != 1 {
+                continue;
+            }
+            let ref_col = refs.iter().next().unwrap();
+
+            let index = aggregate.input.schema().maybe_index_of_column(ref_col);
+            let Some(index) = index else {
+                continue;
+            };
+            let field = aggregate.input.schema().field(index);
+
+            let is_time_index = field.metadata().get(TIME_INDEX_KEY) == Some(&"true".to_string());
+
+            if is_time_index {
+                let rewrite_column = group_expr.clone();
+                let rewritten = rewrite_column
+                    .rewrite(&mut RewriteColumn {
+                        table_name: table_name.to_string(),
+                    })
+                    .with_context(|_| DatafusionSnafu {
+                        context: format!("Rewrite expr failed, expr={:?}", group_expr),
+                    })?
+                    .data;
+                struct RewriteColumn {
+                    table_name: String,
+                }
+
+                impl TreeNodeRewriter for RewriteColumn {
+                    type Node = Expr;
+                    fn f_down(&mut self, node: Self::Node) -> DfResult<Transformed<Self::Node>> {
+                        let Expr::Column(mut column) = node else {
+                            return Ok(Transformed::no(node));
+                        };
+
+                        column.relation = Some(TableReference::bare(self.table_name.clone()));
+
+                        Ok(Transformed::yes(Expr::Column(column)))
+                    }
+                }
+
+                time_window_expr = Some(rewritten);
+                break;
+            }
+        }
+        Ok((ts_col_name, time_window_expr, expected_time_unit, df_schema))
+    } else {
+        // can't found time window expr, return None
+        Ok((ts_col_name, None, expected_time_unit, df_schema))
+    }
+}
+
+/// Find nearest lower bound for time `current` in given `plan` for the time window expr.
+/// i.e. for time window expr being `date_bin(INTERVAL '5 minutes', ts) as time_window` and `current="2021-07-01 00:01:01.000"`,
+/// return `Some("2021-07-01 00:00:00.000")`
+/// if `plan` doesn't contain a `TIME INDEX` column, return `None`
+///
+/// Time window expr is a expr that:
+/// 1. ref only to a time index column
+/// 2. is monotonic increasing
+/// 3. show up in GROUP BY clause
+///
+/// note this plan should only contain one TableScan
+pub async fn find_plan_time_window_bound(
+    plan: &LogicalPlan,
+    current: Timestamp,
+    query_ctx: QueryContextRef,
+    engine: QueryEngineRef,
+) -> Result<(String, Option<Timestamp>, Option<Timestamp>), Error> {
+    // TODO(discord9): find the expr that do time window
+    let catalog_man = engine.engine_state().catalog_manager();
+
+    let (ts_col_name, time_window_expr, expected_time_unit, df_schema) =
+        find_time_window_expr(plan, catalog_man.clone(), query_ctx).await?;
+    // cast current to ts_index's type
+    let new_current = current
+        .convert_to(expected_time_unit)
+        .with_context(|| UnexpectedSnafu {
+            reason: format!("Failed to cast current timestamp {current:?} to {expected_time_unit}"),
+        })?;
+
+    // if no time_window_expr is found, return None
+    if let Some(time_window_expr) = time_window_expr {
+        let lower_bound =
+            find_expr_time_window_lower_bound(&time_window_expr, &df_schema, new_current)?;
+        let upper_bound =
+            find_expr_time_window_upper_bound(&time_window_expr, &df_schema, new_current)?;
+        Ok((ts_col_name, lower_bound, upper_bound))
+    } else {
+        Ok((ts_col_name, None, None))
+    }
+}
+
+/// Find the lower bound of time window in given `expr` and `current` timestamp.
+///
+/// i.e. for `current="2021-07-01 00:01:01.000"` and `expr=date_bin(INTERVAL '5 minutes', ts) as time_window` and `ts_col=ts`,
+/// return `Some("2021-07-01 00:00:00.000")` since it's the lower bound
+/// return `Some("2021-07-01 00:00:00.000")` since it's the lower bound
+/// of current time window given the current timestamp
+///
+/// if return None, meaning this time window have no lower bound
+fn find_expr_time_window_lower_bound(
+    expr: &Expr,
+    df_schema: &DFSchema,
+    current: Timestamp,
+) -> Result<Option<Timestamp>, Error> {
+    let phy_planner = DefaultPhysicalPlanner::default();
+
+    let phy_expr: PhysicalExprRef = phy_planner
+        .create_physical_expr(expr, df_schema, &SessionContext::new().state())
+        .with_context(|_e| DatafusionSnafu {
+            context: format!(
+                "Failed to create physical expression from {expr:?} using {df_schema:?}"
+            ),
+        })?;
+
+    let cur_time_window = eval_ts_to_ts(&phy_expr, df_schema, current)?;
+    let input_time_unit = cur_time_window.unit();
+    Ok(cur_time_window.convert_to(input_time_unit))
+}
+
+/// Find the upper bound for time window expression
+fn find_expr_time_window_upper_bound(
+    expr: &Expr,
+    df_schema: &DFSchema,
+    current: Timestamp,
+) -> Result<Option<Timestamp>, Error> {
+    use std::cmp::Ordering;
+
+    let phy_planner = DefaultPhysicalPlanner::default();
+
+    let phy_expr: PhysicalExprRef = phy_planner
+        .create_physical_expr(expr, df_schema, &SessionContext::new().state())
+        .with_context(|_e| DatafusionSnafu {
+            context: format!(
+                "Failed to create physical expression from {expr:?} using {df_schema:?}"
+            ),
+        })?;
+
+    let cur_time_window = eval_ts_to_ts(&phy_expr, df_schema, current)?;
+
+    // search to find the lower bound
+    let mut offset: i64 = 1;
+    let mut lower_bound = Some(current);
+    let upper_bound;
+    // first expontial probe to found a range for binary search
+    loop {
+        let Some(next_val) = current.value().checked_add(offset) else {
+            // no upper bound if overflow
+            return Ok(None);
+        };
+
+        let next_time_probe = common_time::Timestamp::new(next_val, current.unit());
+
+        let next_time_window = eval_ts_to_ts(&phy_expr, df_schema, next_time_probe)?;
+
+        match next_time_window.cmp(&cur_time_window) {
+            Ordering::Less => {UnexpectedSnafu {
+                reason: format!(
+                    "Unsupported time window expression, expect monotonic increasing for time window expression {expr:?}"
+                ),
+            }
+            .fail()?
+            }
+            Ordering::Equal => {
+                lower_bound = Some(next_time_probe);
+            }
+            Ordering::Greater => {
+                upper_bound = Some(next_time_probe);
+                break
+            }
+        }
+
+        let Some(new_offset) = offset.checked_mul(2) else {
+            // no upper bound if overflow
+            return Ok(None);
+        };
+        offset = new_offset;
+    }
+
+    // binary search for the exact upper bound
+
+    ensure!(lower_bound.map(|v|v.unit())==upper_bound.map(|v|v.unit()), UnexpectedSnafu{
+        reason: format!(" unit mismatch for time window expression {expr:?}, found {lower_bound:?} and {upper_bound:?}"),
+    });
+
+    let output_unit = upper_bound
+        .context(UnexpectedSnafu {
+            reason: "should have lower bound",
+        })?
+        .unit();
+
+    let mut low = lower_bound
+        .context(UnexpectedSnafu {
+            reason: "should have lower bound",
+        })?
+        .value();
+    let mut high = upper_bound
+        .context(UnexpectedSnafu {
+            reason: "should have upper bound",
+        })?
+        .value();
+    while low < high {
+        let mid = (low + high) / 2;
+        let mid_probe = common_time::Timestamp::new(mid, output_unit);
+        let mid_time_window = eval_ts_to_ts(&phy_expr, df_schema, mid_probe)?;
+
+        match mid_time_window.cmp(&cur_time_window) {
+            Ordering::Less => UnexpectedSnafu {
+                reason: format!("Binary search failed for time window expression {expr:?}"),
+            }
+            .fail()?,
+            Ordering::Equal => low = mid + 1,
+            Ordering::Greater => high = mid,
+        }
+    }
+
+    let final_upper_bound_for_time_window = common_time::Timestamp::new(high, output_unit);
+
+    Ok(Some(final_upper_bound_for_time_window))
+}
+
+fn eval_ts_to_ts(
+    phy: &PhysicalExprRef,
+    df_schema: &DFSchema,
+    input_value: Timestamp,
+) -> Result<Timestamp, Error> {
+    let schema_ty = df_schema.field(0).data_type();
+    let schema_cdt = ConcreteDataType::from_arrow_type(schema_ty);
+    let schema_unit = if let ConcreteDataType::Timestamp(ts) = schema_cdt {
+        ts.unit()
+    } else {
+        return UnexpectedSnafu {
+            reason: format!("Expect Timestamp, found {:?}", schema_cdt),
+        }
+        .fail();
+    };
+    let input_value = input_value
+        .convert_to(schema_unit)
+        .with_context(|| UnexpectedSnafu {
+            reason: format!("Failed to convert timestamp {input_value:?} to {schema_unit}"),
+        })?;
+    let ts_vector = match schema_unit {
+        TimeUnit::Second => {
+            TimestampSecondVector::from_vec(vec![input_value.value()]).to_arrow_array()
+        }
+        TimeUnit::Millisecond => {
+            TimestampMillisecondVector::from_vec(vec![input_value.value()]).to_arrow_array()
+        }
+        TimeUnit::Microsecond => {
+            TimestampMicrosecondVector::from_vec(vec![input_value.value()]).to_arrow_array()
+        }
+        TimeUnit::Nanosecond => {
+            TimestampNanosecondVector::from_vec(vec![input_value.value()]).to_arrow_array()
+        }
+    };
+
+    let rb = DfRecordBatch::try_new(df_schema.inner().clone(), vec![ts_vector.clone()])
+        .with_context(|_| ArrowSnafu {
+            context: format!("Failed to create record batch from {df_schema:?} and {ts_vector:?}"),
+        })?;
+
+    let eval_res = phy.evaluate(&rb).with_context(|_| DatafusionSnafu {
+        context: format!("Failed to evaluate physical expression {phy:?} on {rb:?}"),
+    })?;
+
+    if let Some(Some(ts)) = columnar_to_ts_vector(&eval_res)?.first() {
+        Ok(*ts)
+    } else {
+        UnexpectedSnafu {
+            reason: format!(
+                "Expected timestamp in expression {phy:?} but got {:?}",
+                eval_res
+            ),
+        }
+        .fail()?
+    }
+}
+
+// TODO(discord9): a method to found out the precise time window
+
+/// Find out the `Filter` Node corresponding to outermost `WHERE` and add a new filter expr to it
+#[derive(Debug)]
+pub struct AddFilterRewriter {
+    extra_filter: Expr,
+    is_rewritten: bool,
+}
+
+impl AddFilterRewriter {
+    fn new(filter: Expr) -> Self {
+        Self {
+            extra_filter: filter,
+            is_rewritten: false,
+        }
+    }
+}
+
+impl TreeNodeRewriter for AddFilterRewriter {
+    type Node = LogicalPlan;
+    fn f_up(&mut self, node: Self::Node) -> DfResult<Transformed<Self::Node>> {
+        if self.is_rewritten {
+            return Ok(Transformed::no(node));
+        }
+        match node {
+            LogicalPlan::Filter(mut filter) if !filter.having => {
+                filter.predicate = filter.predicate.and(self.extra_filter.clone());
+                self.is_rewritten = true;
+                Ok(Transformed::yes(LogicalPlan::Filter(filter)))
+            }
+            LogicalPlan::TableScan(_) => {
+                // add a new filter
+                let filter =
+                    datafusion_expr::Filter::try_new(self.extra_filter.clone(), Arc::new(node))?;
+                self.is_rewritten = true;
+                Ok(Transformed::yes(LogicalPlan::Filter(filter)))
+            }
+            _ => Ok(Transformed::no(node)),
+        }
+    }
+}
+
+fn df_plan_to_sql(plan: &LogicalPlan) -> Result<String, Error> {
+    /// A dialect that forces all identifiers to be quoted
+    struct ForceQuoteIdentifiers;
+    impl datafusion::sql::unparser::dialect::Dialect for ForceQuoteIdentifiers {
+        fn identifier_quote_style(&self, identifier: &str) -> Option<char> {
+            if identifier.to_lowercase() != identifier {
+                Some('"')
+            } else {
+                None
+            }
+        }
+    }
+    let unparser = Unparser::new(&ForceQuoteIdentifiers);
+    // first make all column qualified
+    let sql = unparser
+        .plan_to_sql(plan)
+        .with_context(|_e| DatafusionSnafu {
+            context: format!("Failed to unparse logical plan {plan:?}"),
+        })?;
+    Ok(sql.to_string())
+}
+
+#[cfg(test)]
+mod test {
+    use datafusion_common::tree_node::TreeNode;
+    use pretty_assertions::assert_eq;
+    use session::context::QueryContext;
+
+    use super::{sql_to_df_plan, *};
+    use crate::recording_rules::{df_plan_to_sql, AddFilterRewriter};
+    use crate::test_utils::create_test_query_engine;
+
+    #[tokio::test]
+    async fn test_sql_plan_convert() {
+        let query_engine = create_test_query_engine();
+        let ctx = QueryContext::arc();
+        let old = r#"SELECT "NUMBER" FROM "UPPERCASE_NUMBERS_WITH_TS""#;
+        let new = sql_to_df_plan(ctx.clone(), query_engine.clone(), old, false)
+            .await
+            .unwrap();
+        let new_sql = df_plan_to_sql(&new).unwrap();
+
+        assert_eq!(
+            r#"SELECT "UPPERCASE_NUMBERS_WITH_TS"."NUMBER" FROM "UPPERCASE_NUMBERS_WITH_TS""#,
+            new_sql
+        );
+    }
+
+    #[tokio::test]
+    async fn test_add_filter() {
+        let testcases = vec![
+            (
+                "SELECT number FROM numbers_with_ts GROUP BY number","SELECT numbers_with_ts.number FROM numbers_with_ts WHERE (number > 4) GROUP BY numbers_with_ts.number"
+            ),
+            (
+                "SELECT number FROM numbers_with_ts WHERE number < 2 OR number >10",
+                "SELECT numbers_with_ts.number FROM numbers_with_ts WHERE ((numbers_with_ts.number < 2) OR (numbers_with_ts.number > 10)) AND (number > 4)"
+            ),
+            (
+                "SELECT date_bin('5 minutes', ts) as time_window FROM numbers_with_ts GROUP BY time_window",
+                "SELECT date_bin('5 minutes', numbers_with_ts.ts) AS time_window FROM numbers_with_ts WHERE (number > 4) GROUP BY date_bin('5 minutes', numbers_with_ts.ts)"
+            )
+        ];
+        use datafusion_expr::{col, lit};
+        let query_engine = create_test_query_engine();
+        let ctx = QueryContext::arc();
+
+        for (before, after) in testcases {
+            let sql = before;
+            let plan = sql_to_df_plan(ctx.clone(), query_engine.clone(), sql, false)
+                .await
+                .unwrap();
+
+            let mut add_filter = AddFilterRewriter::new(col("number").gt(lit(4u32)));
+            let plan = plan.rewrite(&mut add_filter).unwrap().data;
+            let new_sql = df_plan_to_sql(&plan).unwrap();
+            assert_eq!(after, new_sql);
+        }
+    }
+
+    #[tokio::test]
+    async fn test_plan_time_window_lower_bound() {
+        use datafusion_expr::{col, lit};
+        let query_engine = create_test_query_engine();
+        let ctx = QueryContext::arc();
+
+        let testcases = [
+            // same alias is not same column
+            (
+                "SELECT arrow_cast(date_bin(INTERVAL '1 MINS', numbers_with_ts.ts), 'Timestamp(Second, None)') AS ts FROM numbers_with_ts GROUP BY ts;",
+                Timestamp::new(1740394109, TimeUnit::Second),
+                (
+                    "ts".to_string(),
+                    Some(Timestamp::new(1740394109000, TimeUnit::Millisecond)),
+                    Some(Timestamp::new(1740394109001, TimeUnit::Millisecond)),
+                ),
+                r#"SELECT arrow_cast(date_bin(INTERVAL '1 MINS', numbers_with_ts.ts), 'Timestamp(Second, None)') AS ts FROM numbers_with_ts WHERE ((ts >= CAST('2025-02-24 10:48:29' AS TIMESTAMP)) AND (ts <= CAST('2025-02-24 10:48:29.001' AS TIMESTAMP))) GROUP BY numbers_with_ts.ts"#
+            ),
+            // complex time window index
+            (
+                "SELECT arrow_cast(date_bin(INTERVAL '1 MINS', numbers_with_ts.ts), 'Timestamp(Second, None)') AS time_window FROM numbers_with_ts GROUP BY time_window;",
+                Timestamp::new(1740394109, TimeUnit::Second),
+                (
+                    "ts".to_string(),
+                    Some(Timestamp::new(1740394080, TimeUnit::Second)),
+                    Some(Timestamp::new(1740394140, TimeUnit::Second)),
+                ),
+                "SELECT arrow_cast(date_bin(INTERVAL '1 MINS', numbers_with_ts.ts), 'Timestamp(Second, None)') AS time_window FROM numbers_with_ts WHERE ((ts >= CAST('2025-02-24 10:48:00' AS TIMESTAMP)) AND (ts <= CAST('2025-02-24 10:49:00' AS TIMESTAMP))) GROUP BY arrow_cast(date_bin(INTERVAL '1 MINS', numbers_with_ts.ts), 'Timestamp(Second, None)')"
+            ),
+            // no time index
+            (
+                "SELECT date_bin('5 minutes', ts) FROM numbers_with_ts;",
+                Timestamp::new(23, TimeUnit::Millisecond),
+                ("ts".to_string(), None, None),
+                "SELECT date_bin('5 minutes', ts) FROM numbers_with_ts;"
+            ),
+            // time index
+            (
+                "SELECT date_bin('5 minutes', ts) as time_window FROM numbers_with_ts GROUP BY time_window;",
+                Timestamp::new(23, TimeUnit::Nanosecond),
+                (
+                    "ts".to_string(),
+                    Some(Timestamp::new(0, TimeUnit::Millisecond)),
+                    Some(Timestamp::new(300000, TimeUnit::Millisecond)),
+                ),
+                "SELECT date_bin('5 minutes', numbers_with_ts.ts) AS time_window FROM numbers_with_ts WHERE ((ts >= CAST('1970-01-01 00:00:00' AS TIMESTAMP)) AND (ts <= CAST('1970-01-01 00:05:00' AS TIMESTAMP))) GROUP BY date_bin('5 minutes', numbers_with_ts.ts)"
+            ),
+            // on spot
+            (
+                "SELECT date_bin('5 minutes', ts) as time_window FROM numbers_with_ts GROUP BY time_window;",
+                Timestamp::new(0, TimeUnit::Nanosecond),
+                (
+                    "ts".to_string(),
+                    Some(Timestamp::new(0, TimeUnit::Millisecond)),
+                    Some(Timestamp::new(300000, TimeUnit::Millisecond)),
+                ),
+                "SELECT date_bin('5 minutes', numbers_with_ts.ts) AS time_window FROM numbers_with_ts WHERE ((ts >= CAST('1970-01-01 00:00:00' AS TIMESTAMP)) AND (ts <= CAST('1970-01-01 00:05:00' AS TIMESTAMP))) GROUP BY date_bin('5 minutes', numbers_with_ts.ts)"
+            ),
+            // different time unit
+            (
+                "SELECT date_bin('5 minutes', ts) as time_window FROM numbers_with_ts GROUP BY time_window;",
+                Timestamp::new(23_000_000, TimeUnit::Nanosecond),
+                (
+                    "ts".to_string(),
+                    Some(Timestamp::new(0, TimeUnit::Millisecond)),
+                    Some(Timestamp::new(300000, TimeUnit::Millisecond)),
+                ),
+                "SELECT date_bin('5 minutes', numbers_with_ts.ts) AS time_window FROM numbers_with_ts WHERE ((ts >= CAST('1970-01-01 00:00:00' AS TIMESTAMP)) AND (ts <= CAST('1970-01-01 00:05:00' AS TIMESTAMP))) GROUP BY date_bin('5 minutes', numbers_with_ts.ts)"
+            ),
+            // time index with other fields
+            (
+                "SELECT sum(number) as sum_up, date_bin('5 minutes', ts) as time_window FROM numbers_with_ts GROUP BY time_window;",
+                Timestamp::new(23, TimeUnit::Millisecond),
+                (
+                    "ts".to_string(),
+                    Some(Timestamp::new(0, TimeUnit::Millisecond)),
+                    Some(Timestamp::new(300000, TimeUnit::Millisecond)),
+                ),
+                "SELECT sum(numbers_with_ts.number) AS sum_up, date_bin('5 minutes', numbers_with_ts.ts) AS time_window FROM numbers_with_ts WHERE ((ts >= CAST('1970-01-01 00:00:00' AS TIMESTAMP)) AND (ts <= CAST('1970-01-01 00:05:00' AS TIMESTAMP))) GROUP BY date_bin('5 minutes', numbers_with_ts.ts)"
+            ),
+            // time index with other pks
+            (
+                "SELECT number, date_bin('5 minutes', ts) as time_window FROM numbers_with_ts GROUP BY time_window, number;",
+                Timestamp::new(23, TimeUnit::Millisecond),
+                (
+                    "ts".to_string(),
+                    Some(Timestamp::new(0, TimeUnit::Millisecond)),
+                    Some(Timestamp::new(300000, TimeUnit::Millisecond)),
+                ),
+                "SELECT numbers_with_ts.number, date_bin('5 minutes', numbers_with_ts.ts) AS time_window FROM numbers_with_ts WHERE ((ts >= CAST('1970-01-01 00:00:00' AS TIMESTAMP)) AND (ts <= CAST('1970-01-01 00:05:00' AS TIMESTAMP))) GROUP BY date_bin('5 minutes', numbers_with_ts.ts), numbers_with_ts.number"
+            ),
+            // subquery
+            (
+                "SELECT number, time_window FROM (SELECT number, date_bin('5 minutes', ts) as time_window FROM numbers_with_ts GROUP BY time_window, number);",
+                Timestamp::new(23, TimeUnit::Millisecond),
+                (
+                    "ts".to_string(),
+                    Some(Timestamp::new(0, TimeUnit::Millisecond)),
+                    Some(Timestamp::new(300000, TimeUnit::Millisecond)),
+                ),
+                "SELECT numbers_with_ts.number, time_window FROM (SELECT numbers_with_ts.number, date_bin('5 minutes', numbers_with_ts.ts) AS time_window FROM numbers_with_ts WHERE ((ts >= CAST('1970-01-01 00:00:00' AS TIMESTAMP)) AND (ts <= CAST('1970-01-01 00:05:00' AS TIMESTAMP))) GROUP BY date_bin('5 minutes', numbers_with_ts.ts), numbers_with_ts.number)"
+            ),
+            // cte
+            (
+                "with cte as (select number, date_bin('5 minutes', ts) as time_window from numbers_with_ts GROUP BY time_window, number) select number, time_window from cte;",
+                Timestamp::new(23, TimeUnit::Millisecond),
+                (
+                    "ts".to_string(),
+                    Some(Timestamp::new(0, TimeUnit::Millisecond)),
+                    Some(Timestamp::new(300000, TimeUnit::Millisecond)),
+                ),
+                "SELECT cte.number, cte.time_window FROM (SELECT numbers_with_ts.number, date_bin('5 minutes', numbers_with_ts.ts) AS time_window FROM numbers_with_ts WHERE ((ts >= CAST('1970-01-01 00:00:00' AS TIMESTAMP)) AND (ts <= CAST('1970-01-01 00:05:00' AS TIMESTAMP))) GROUP BY date_bin('5 minutes', numbers_with_ts.ts), numbers_with_ts.number) AS cte"
+            ),
+            // complex subquery without alias
+            (
+                "SELECT sum(number), number, date_bin('5 minutes', ts) as time_window, bucket_name FROM (SELECT number, ts, case when number < 5 THEN 'bucket_0_5' when number >= 5 THEN 'bucket_5_inf' END as bucket_name FROM numbers_with_ts) GROUP BY number, time_window, bucket_name;",
+                Timestamp::new(23, TimeUnit::Millisecond),
+                (
+                    "ts".to_string(),
+                    Some(Timestamp::new(0, TimeUnit::Millisecond)),
+                    Some(Timestamp::new(300000, TimeUnit::Millisecond)),
+                ),
+                "SELECT sum(numbers_with_ts.number), numbers_with_ts.number, date_bin('5 minutes', numbers_with_ts.ts) AS time_window, bucket_name FROM (SELECT numbers_with_ts.number, numbers_with_ts.ts, CASE WHEN (numbers_with_ts.number < 5) THEN 'bucket_0_5' WHEN (numbers_with_ts.number >= 5) THEN 'bucket_5_inf' END AS bucket_name FROM numbers_with_ts WHERE ((ts >= CAST('1970-01-01 00:00:00' AS TIMESTAMP)) AND (ts <= CAST('1970-01-01 00:05:00' AS TIMESTAMP)))) GROUP BY numbers_with_ts.number, date_bin('5 minutes', numbers_with_ts.ts), bucket_name"
+            ),
+            // complex subquery alias
+            (
+                "SELECT sum(number), number, date_bin('5 minutes', ts) as time_window, bucket_name FROM (SELECT number, ts, case when number < 5 THEN 'bucket_0_5' when number >= 5 THEN 'bucket_5_inf' END as bucket_name FROM numbers_with_ts) as cte GROUP BY number, time_window, bucket_name;",
+                Timestamp::new(23, TimeUnit::Millisecond),
+                (
+                    "ts".to_string(),
+                    Some(Timestamp::new(0, TimeUnit::Millisecond)),
+                    Some(Timestamp::new(300000, TimeUnit::Millisecond)),
+                ),
+                "SELECT sum(cte.number), cte.number, date_bin('5 minutes', cte.ts) AS time_window, cte.bucket_name FROM (SELECT numbers_with_ts.number, numbers_with_ts.ts, CASE WHEN (numbers_with_ts.number < 5) THEN 'bucket_0_5' WHEN (numbers_with_ts.number >= 5) THEN 'bucket_5_inf' END AS bucket_name FROM numbers_with_ts WHERE ((ts >= CAST('1970-01-01 00:00:00' AS TIMESTAMP)) AND (ts <= CAST('1970-01-01 00:05:00' AS TIMESTAMP)))) AS cte GROUP BY cte.number, date_bin('5 minutes', cte.ts), cte.bucket_name"
+            ),
+        ];
+
+        for (sql, current, expected, expected_unparsed) in testcases {
+            let plan = sql_to_df_plan(ctx.clone(), query_engine.clone(), sql, true)
+                .await
+                .unwrap();
+
+            let real =
+                find_plan_time_window_bound(&plan, current, ctx.clone(), query_engine.clone())
+                    .await
+                    .unwrap();
+            assert_eq!(expected, real);
+
+            let plan = sql_to_df_plan(ctx.clone(), query_engine.clone(), sql, false)
+                .await
+                .unwrap();
+            let (col_name, lower, upper) = real;
+            let new_sql = if lower.is_some() {
+                let to_df_literal = |value| {
+                    let value = Value::from(value);
+
+                    value.try_to_scalar_value(&value.data_type()).unwrap()
+                };
+                let lower = to_df_literal(lower.unwrap());
+                let upper = to_df_literal(upper.unwrap());
+                let expr = col(&col_name)
+                    .gt_eq(lit(lower))
+                    .and(col(&col_name).lt_eq(lit(upper)));
+                let mut add_filter = AddFilterRewriter::new(expr);
+                let plan = plan.rewrite(&mut add_filter).unwrap().data;
+                df_plan_to_sql(&plan).unwrap()
+            } else {
+                sql.to_string()
+            };
+            assert_eq!(expected_unparsed, new_sql);
+        }
+    }
+}

src/flow/src/recording_rules/engine.rs

@@ -0,0 +1,815 @@
+// 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::collections::{BTreeMap, HashMap, HashSet};
+use std::sync::Arc;
+use std::time::{Duration, SystemTime, UNIX_EPOCH};
+
+use api::v1::flow::FlowResponse;
+use common_error::ext::BoxedError;
+use common_meta::ddl::create_flow::FlowType;
+use common_meta::key::flow::FlowMetadataManagerRef;
+use common_meta::key::table_info::TableInfoManager;
+use common_meta::key::TableMetadataManagerRef;
+use common_telemetry::tracing::warn;
+use common_telemetry::{debug, info};
+use common_time::Timestamp;
+use datafusion::sql::unparser::expr_to_sql;
+use datafusion_common::tree_node::TreeNode;
+use datatypes::value::Value;
+use query::QueryEngineRef;
+use session::context::QueryContextRef;
+use snafu::{ensure, OptionExt, ResultExt};
+use store_api::storage::RegionId;
+use table::metadata::TableId;
+use tokio::sync::oneshot::error::TryRecvError;
+use tokio::sync::{oneshot, RwLock};
+use tokio::time::Instant;
+
+use super::frontend_client::FrontendClient;
+use super::{df_plan_to_sql, AddFilterRewriter, TimeWindowExpr};
+use crate::adapter::{CreateFlowArgs, FlowId, TableName};
+use crate::error::{
+    DatafusionSnafu, DatatypesSnafu, ExternalSnafu, FlowAlreadyExistSnafu, InternalSnafu,
+    TimeSnafu, UnexpectedSnafu,
+};
+use crate::metrics::{METRIC_FLOW_RULE_ENGINE_QUERY_TIME, METRIC_FLOW_RULE_ENGINE_SLOW_QUERY};
+use crate::recording_rules::{find_time_window_expr, sql_to_df_plan};
+use crate::Error;
+
+/// TODO(discord9): make those constants configurable
+/// The default rule engine query timeout is 10 minutes
+pub const DEFAULT_RULE_ENGINE_QUERY_TIMEOUT: Duration = Duration::from_secs(10 * 60);
+
+/// will output a warn log for any query that runs for more that 1 minutes, and also every 1 minutes when that query is still running
+pub const SLOW_QUERY_THRESHOLD: Duration = Duration::from_secs(60);
+
+/// TODO(discord9): determine how to configure refresh rate
+pub struct RecordingRuleEngine {
+    tasks: RwLock<BTreeMap<FlowId, RecordingRuleTask>>,
+    shutdown_txs: RwLock<BTreeMap<FlowId, oneshot::Sender<()>>>,
+    frontend_client: Arc<FrontendClient>,
+    flow_metadata_manager: FlowMetadataManagerRef,
+    table_meta: TableMetadataManagerRef,
+    engine: QueryEngineRef,
+}
+
+impl RecordingRuleEngine {
+    pub fn new(
+        frontend_client: Arc<FrontendClient>,
+        engine: QueryEngineRef,
+        flow_metadata_manager: FlowMetadataManagerRef,
+        table_meta: TableMetadataManagerRef,
+    ) -> Self {
+        Self {
+            tasks: Default::default(),
+            shutdown_txs: Default::default(),
+            frontend_client,
+            flow_metadata_manager,
+            table_meta,
+            engine,
+        }
+    }
+
+    pub async fn handle_inserts(
+        &self,
+        request: api::v1::region::InsertRequests,
+    ) -> Result<FlowResponse, Error> {
+        let table_info_mgr = self.table_meta.table_info_manager();
+        let mut group_by_table_name: HashMap<TableName, Vec<api::v1::Rows>> = HashMap::new();
+        for r in request.requests {
+            let tid = RegionId::from(r.region_id).table_id();
+            let name = get_table_name(table_info_mgr, &tid).await?;
+            let entry = group_by_table_name.entry(name).or_default();
+            if let Some(rows) = r.rows {
+                entry.push(rows);
+            }
+        }
+
+        for (_flow_id, task) in self.tasks.read().await.iter() {
+            let src_table_names = &task.source_table_names;
+
+            for src_table_name in src_table_names {
+                if let Some(entry) = group_by_table_name.get(src_table_name) {
+                    let Some(expr) = &task.time_window_expr else {
+                        continue;
+                    };
+                    let involved_time_windows = expr.handle_rows(entry.clone()).await?;
+                    let mut state = task.state.write().await;
+                    state
+                        .dirty_time_windows
+                        .add_lower_bounds(involved_time_windows.into_iter());
+                }
+            }
+        }
+
+        Ok(Default::default())
+    }
+}
+
+async fn get_table_name(zelf: &TableInfoManager, table_id: &TableId) -> Result<TableName, Error> {
+    zelf.get(*table_id)
+        .await
+        .map_err(BoxedError::new)
+        .context(ExternalSnafu)?
+        .with_context(|| UnexpectedSnafu {
+            reason: format!("Table id = {:?}, couldn't found table name", table_id),
+        })
+        .map(|name| name.table_name())
+        .map(|name| [name.catalog_name, name.schema_name, name.table_name])
+}
+
+const MIN_REFRESH_DURATION: Duration = Duration::new(5, 0);
+
+impl RecordingRuleEngine {
+    pub async fn create_flow(&self, args: CreateFlowArgs) -> Result<Option<FlowId>, Error> {
+        let CreateFlowArgs {
+            flow_id,
+            sink_table_name,
+            source_table_ids,
+            create_if_not_exists,
+            or_replace,
+            expire_after,
+            comment: _,
+            sql,
+            flow_options,
+            query_ctx,
+        } = args;
+
+        // or replace logic
+        {
+            let is_exist = self.tasks.read().await.contains_key(&flow_id);
+            match (create_if_not_exists, or_replace, is_exist) {
+                // if replace, ignore that old flow exists
+                (_, true, true) => {
+                    info!("Replacing flow with id={}", flow_id);
+                }
+                (false, false, true) => FlowAlreadyExistSnafu { id: flow_id }.fail()?,
+                // already exists, and not replace, return None
+                (true, false, true) => {
+                    info!("Flow with id={} already exists, do nothing", flow_id);
+                    return Ok(None);
+                }
+
+                // continue as normal
+                (_, _, false) => (),
+            }
+        }
+
+        let flow_type = flow_options.get(FlowType::FLOW_TYPE_KEY);
+
+        ensure!(
+            flow_type == Some(&FlowType::RecordingRule.to_string()) || flow_type.is_none(),
+            UnexpectedSnafu {
+                reason: format!("Flow type is not RecordingRule nor None, got {flow_type:?}")
+            }
+        );
+
+        let Some(query_ctx) = query_ctx else {
+            UnexpectedSnafu {
+                reason: "Query context is None".to_string(),
+            }
+            .fail()?
+        };
+        let query_ctx = Arc::new(query_ctx);
+        let mut source_table_names = Vec::new();
+        for src_id in source_table_ids {
+            let table_name = self
+                .table_meta
+                .table_info_manager()
+                .get(src_id)
+                .await
+                .map_err(BoxedError::new)
+                .context(ExternalSnafu)?
+                .with_context(|| UnexpectedSnafu {
+                    reason: format!("Table id = {:?}, couldn't found table name", src_id),
+                })
+                .map(|name| name.table_name())
+                .map(|name| [name.catalog_name, name.schema_name, name.table_name])?;
+            source_table_names.push(table_name);
+        }
+
+        let (tx, rx) = oneshot::channel();
+
+        let plan = sql_to_df_plan(query_ctx.clone(), self.engine.clone(), &sql, true).await?;
+        let (column_name, time_window_expr, _, df_schema) = find_time_window_expr(
+            &plan,
+            self.engine.engine_state().catalog_manager().clone(),
+            query_ctx.clone(),
+        )
+        .await?;
+
+        let phy_expr = time_window_expr
+            .map(|expr| TimeWindowExpr::from_expr(&expr, &column_name, &df_schema))
+            .transpose()?;
+
+        info!("Flow id={}, found time window expr={:?}", flow_id, phy_expr);
+
+        let task = RecordingRuleTask::new(
+            flow_id,
+            &sql,
+            phy_expr,
+            expire_after,
+            sink_table_name,
+            source_table_names,
+            query_ctx,
+            rx,
+        );
+
+        let task_inner = task.clone();
+        let engine = self.engine.clone();
+        let frontend = self.frontend_client.clone();
+
+        // TODO(discord9): also save handle & use time wheel or what for better
+        let _handle = common_runtime::spawn_global(async move {
+            match task_inner.start_executing(engine, frontend).await {
+                Ok(()) => info!("Flow {} shutdown", task_inner.flow_id),
+                Err(err) => common_telemetry::error!(
+                    "Flow {} encounter unrecoverable error: {err:?}",
+                    task_inner.flow_id
+                ),
+            }
+        });
+
+        // TODO(discord9): deal with replace logic
+        let replaced_old_task_opt = self.tasks.write().await.insert(flow_id, task);
+        drop(replaced_old_task_opt);
+
+        self.shutdown_txs.write().await.insert(flow_id, tx);
+
+        Ok(Some(flow_id))
+    }
+
+    pub async fn remove_flow(&self, flow_id: FlowId) -> Result<(), Error> {
+        if self.tasks.write().await.remove(&flow_id).is_none() {
+            warn!("Flow {flow_id} not found in tasks")
+        }
+        let Some(tx) = self.shutdown_txs.write().await.remove(&flow_id) else {
+            UnexpectedSnafu {
+                reason: format!("Can't found shutdown tx for flow {flow_id}"),
+            }
+            .fail()?
+        };
+        if tx.send(()).is_err() {
+            warn!("Fail to shutdown flow {flow_id} due to receiver already dropped, maybe flow {flow_id} is already dropped?")
+        }
+        Ok(())
+    }
+}
+
+#[derive(Debug, Clone)]
+pub struct RecordingRuleTask {
+    pub flow_id: FlowId,
+    query: String,
+    pub time_window_expr: Option<TimeWindowExpr>,
+    /// in seconds
+    pub expire_after: Option<i64>,
+    sink_table_name: [String; 3],
+    source_table_names: HashSet<[String; 3]>,
+    state: Arc<RwLock<RecordingRuleState>>,
+}
+
+impl RecordingRuleTask {
+    #[allow(clippy::too_many_arguments)]
+    pub fn new(
+        flow_id: FlowId,
+        query: &str,
+        time_window_expr: Option<TimeWindowExpr>,
+        expire_after: Option<i64>,
+        sink_table_name: [String; 3],
+        source_table_names: Vec<[String; 3]>,
+        query_ctx: QueryContextRef,
+        shutdown_rx: oneshot::Receiver<()>,
+    ) -> Self {
+        Self {
+            flow_id,
+            query: query.to_string(),
+            time_window_expr,
+            expire_after,
+            sink_table_name,
+            source_table_names: source_table_names.into_iter().collect(),
+            state: Arc::new(RwLock::new(RecordingRuleState::new(query_ctx, shutdown_rx))),
+        }
+    }
+}
+impl RecordingRuleTask {
+    /// This should be called in a new tokio task
+    pub async fn start_executing(
+        &self,
+        engine: QueryEngineRef,
+        frontend_client: Arc<FrontendClient>,
+    ) -> Result<(), Error> {
+        // only first query don't need upper bound
+        let mut is_first = true;
+
+        loop {
+            // FIXME(discord9): test if need upper bound also works
+            let new_query = self.gen_query_with_time_window(engine.clone()).await?;
+
+            let insert_into = if let Some(new_query) = new_query {
+                format!(
+                    "INSERT INTO {}.{}.{} {}",
+                    self.sink_table_name[0],
+                    self.sink_table_name[1],
+                    self.sink_table_name[2],
+                    new_query
+                )
+            } else {
+                tokio::time::sleep(MIN_REFRESH_DURATION).await;
+                continue;
+            };
+
+            if is_first {
+                is_first = false;
+            }
+
+            let instant = Instant::now();
+            let flow_id = self.flow_id;
+            let db_client = frontend_client.get_database_client().await?;
+            let peer_addr = db_client.peer.addr;
+            debug!(
+                "Executing flow {flow_id}(expire_after={:?} secs) on {:?} with query {}",
+                self.expire_after, peer_addr, &insert_into
+            );
+
+            let timer = METRIC_FLOW_RULE_ENGINE_QUERY_TIME
+                .with_label_values(&[flow_id.to_string().as_str()])
+                .start_timer();
+
+            let res = db_client.database.sql(&insert_into).await;
+            drop(timer);
+
+            let elapsed = instant.elapsed();
+            if let Ok(res1) = &res {
+                debug!(
+                    "Flow {flow_id} executed, result: {res1:?}, elapsed: {:?}",
+                    elapsed
+                );
+            } else if let Err(res) = &res {
+                warn!(
+                    "Failed to execute Flow {flow_id} on frontend {}, result: {res:?}, elapsed: {:?} with query: {}",
+                    peer_addr, elapsed, &insert_into
+                );
+            }
+
+            // record slow query
+            if elapsed >= SLOW_QUERY_THRESHOLD {
+                warn!(
+                    "Flow {flow_id} on frontend {} executed for {:?} before complete, query: {}",
+                    peer_addr, elapsed, &insert_into
+                );
+                METRIC_FLOW_RULE_ENGINE_SLOW_QUERY
+                    .with_label_values(&[flow_id.to_string().as_str(), &insert_into, &peer_addr])
+                    .observe(elapsed.as_secs_f64());
+            }
+
+            self.state
+                .write()
+                .await
+                .after_query_exec(elapsed, res.is_ok());
+            // drop the result to free client-related resources
+            drop(res);
+
+            let sleep_until = {
+                let mut state = self.state.write().await;
+                match state.shutdown_rx.try_recv() {
+                    Ok(()) => break Ok(()),
+                    Err(TryRecvError::Closed) => {
+                        warn!("Unexpected shutdown flow {flow_id}, shutdown anyway");
+                        break Ok(());
+                    }
+                    Err(TryRecvError::Empty) => (),
+                }
+                state.get_next_start_query_time(None)
+            };
+            tokio::time::sleep_until(sleep_until).await;
+        }
+    }
+
+    /// will merge and use the first ten time window in query
+    async fn gen_query_with_time_window(
+        &self,
+        engine: QueryEngineRef,
+    ) -> Result<Option<String>, Error> {
+        let query_ctx = self.state.read().await.query_ctx.clone();
+        let start = SystemTime::now();
+        let since_the_epoch = start
+            .duration_since(UNIX_EPOCH)
+            .expect("Time went backwards");
+        let low_bound = self
+            .expire_after
+            .map(|e| since_the_epoch.as_secs() - e as u64)
+            .unwrap_or(u64::MIN);
+
+        let low_bound = Timestamp::new_second(low_bound as i64);
+
+        // TODO(discord9): use time window expr to get the precise expire lower bound
+        let expire_time_window_bound = self
+            .time_window_expr
+            .as_ref()
+            .map(|expr| expr.eval(low_bound))
+            .transpose()?;
+
+        let new_sql = {
+            let expr = {
+                match expire_time_window_bound {
+                    Some((Some(l), Some(u))) => {
+                        let window_size = u.sub(&l).with_context(|| UnexpectedSnafu {
+                            reason: format!("Can't get window size from {u:?} - {l:?}"),
+                        })?;
+                        let col_name = self
+                            .time_window_expr
+                            .as_ref()
+                            .map(|expr| expr.column_name.clone())
+                            .with_context(|| UnexpectedSnafu {
+                                reason: format!(
+                                    "Flow id={:?}, Failed to get column name from time window expr",
+                                    self.flow_id
+                                ),
+                            })?;
+
+                        self.state
+                            .write()
+                            .await
+                            .dirty_time_windows
+                            .gen_filter_exprs(&col_name, Some(l), window_size, self)?
+                    }
+                    _ => {
+                        debug!(
+                            "Flow id = {:?}, can't get window size: precise_lower_bound={expire_time_window_bound:?}, using the same query", self.flow_id
+                        );
+                        // since no time window lower/upper bound is found, just return the original query
+                        return Ok(Some(self.query.clone()));
+                    }
+                }
+            };
+
+            debug!(
+                "Flow id={:?}, Generated filter expr: {:?}",
+                self.flow_id,
+                expr.as_ref()
+                    .map(|expr| expr_to_sql(expr).with_context(|_| DatafusionSnafu {
+                        context: format!("Failed to generate filter expr from {expr:?}"),
+                    }))
+                    .transpose()?
+                    .map(|s| s.to_string())
+            );
+
+            let Some(expr) = expr else {
+                // no new data, hence no need to update
+                debug!("Flow id={:?}, no new data, not update", self.flow_id);
+                return Ok(None);
+            };
+
+            let mut add_filter = AddFilterRewriter::new(expr);
+            // make a not optimized plan for clearer unparse
+            let plan =
+                sql_to_df_plan(query_ctx.clone(), engine.clone(), &self.query, false).await?;
+            let plan = plan
+                .clone()
+                .rewrite(&mut add_filter)
+                .with_context(|_| DatafusionSnafu {
+                    context: format!("Failed to rewrite plan {plan:?}"),
+                })?
+                .data;
+            df_plan_to_sql(&plan)?
+        };
+
+        Ok(Some(new_sql))
+    }
+}
+
+#[derive(Debug)]
+pub struct RecordingRuleState {
+    query_ctx: QueryContextRef,
+    /// last query complete time
+    last_update_time: Instant,
+    /// last time query duration
+    last_query_duration: Duration,
+    /// Dirty Time windows need to be updated
+    /// mapping of `start -> end` and non-overlapping
+    dirty_time_windows: DirtyTimeWindows,
+    exec_state: ExecState,
+    shutdown_rx: oneshot::Receiver<()>,
+}
+
+#[derive(Debug, Clone, Default)]
+pub struct DirtyTimeWindows {
+    windows: BTreeMap<Timestamp, Option<Timestamp>>,
+}
+
+fn to_df_literal(value: Timestamp) -> Result<datafusion_common::ScalarValue, Error> {
+    let value = Value::from(value);
+    let value = value
+        .try_to_scalar_value(&value.data_type())
+        .with_context(|_| DatatypesSnafu {
+            extra: format!("Failed to convert to scalar value: {}", value),
+        })?;
+    Ok(value)
+}
+
+impl DirtyTimeWindows {
+    /// Time window merge distance
+    const MERGE_DIST: i32 = 3;
+
+    /// Maximum number of filters allowed in a single query
+    const MAX_FILTER_NUM: usize = 20;
+
+    /// Add lower bounds to the dirty time windows. Upper bounds are ignored.
+    ///
+    /// # Arguments
+    ///
+    /// * `lower_bounds` - An iterator of lower bounds to be added.
+    pub fn add_lower_bounds(&mut self, lower_bounds: impl Iterator<Item = Timestamp>) {
+        for lower_bound in lower_bounds {
+            let entry = self.windows.entry(lower_bound);
+            entry.or_insert(None);
+        }
+    }
+
+    /// Generate all filter expressions consuming all time windows
+    pub fn gen_filter_exprs(
+        &mut self,
+        col_name: &str,
+        expire_lower_bound: Option<Timestamp>,
+        window_size: chrono::Duration,
+        task_ctx: &RecordingRuleTask,
+    ) -> Result<Option<datafusion_expr::Expr>, Error> {
+        debug!(
+            "expire_lower_bound: {:?}, window_size: {:?}",
+            expire_lower_bound.map(|t| t.to_iso8601_string()),
+            window_size
+        );
+        self.merge_dirty_time_windows(window_size, expire_lower_bound)?;
+
+        if self.windows.len() > Self::MAX_FILTER_NUM {
+            let first_time_window = self.windows.first_key_value();
+            let last_time_window = self.windows.last_key_value();
+            warn!(
+                "Flow id = {:?}, too many time windows: {}, only the first {} are taken for this query, the group by expression might be wrong. Time window expr={:?}, expire_after={:?}, first_time_window={:?}, last_time_window={:?}, the original query: {:?}",
+                task_ctx.flow_id,
+                self.windows.len(),
+                Self::MAX_FILTER_NUM,
+                task_ctx.time_window_expr,
+                task_ctx.expire_after,
+                first_time_window,
+                last_time_window,
+                task_ctx.query
+            );
+        }
+
+        // get the first `MAX_FILTER_NUM` time windows
+        let nth = self
+            .windows
+            .iter()
+            .nth(Self::MAX_FILTER_NUM)
+            .map(|(key, _)| *key);
+        let first_nth = {
+            if let Some(nth) = nth {
+                let mut after = self.windows.split_off(&nth);
+                std::mem::swap(&mut self.windows, &mut after);
+
+                after
+            } else {
+                std::mem::take(&mut self.windows)
+            }
+        };
+
+        let mut expr_lst = vec![];
+        for (start, end) in first_nth.into_iter() {
+            debug!(
+                "Time window start: {:?}, end: {:?}",
+                start.to_iso8601_string(),
+                end.map(|t| t.to_iso8601_string())
+            );
+
+            use datafusion_expr::{col, lit};
+            let lower = to_df_literal(start)?;
+            let upper = end.map(to_df_literal).transpose()?;
+            let expr = if let Some(upper) = upper {
+                col(col_name)
+                    .gt_eq(lit(lower))
+                    .and(col(col_name).lt(lit(upper)))
+            } else {
+                col(col_name).gt_eq(lit(lower))
+            };
+            expr_lst.push(expr);
+        }
+        let expr = expr_lst.into_iter().reduce(|a, b| a.or(b));
+        Ok(expr)
+    }
+
+    /// Merge time windows that overlaps or get too close
+    pub fn merge_dirty_time_windows(
+        &mut self,
+        window_size: chrono::Duration,
+        expire_lower_bound: Option<Timestamp>,
+    ) -> Result<(), Error> {
+        let mut new_windows = BTreeMap::new();
+
+        let mut prev_tw = None;
+        for (lower_bound, upper_bound) in std::mem::take(&mut self.windows) {
+            // filter out expired time window
+            if let Some(expire_lower_bound) = expire_lower_bound {
+                if lower_bound <= expire_lower_bound {
+                    continue;
+                }
+            }
+
+            let Some(prev_tw) = &mut prev_tw else {
+                prev_tw = Some((lower_bound, upper_bound));
+                continue;
+            };
+
+            let std_window_size = window_size.to_std().map_err(|e| {
+                InternalSnafu {
+                    reason: e.to_string(),
+                }
+                .build()
+            })?;
+
+            // if cur.lower - prev.upper <= window_size * 2, merge
+            let prev_upper = prev_tw
+                .1
+                .unwrap_or(prev_tw.0.add_duration(std_window_size).context(TimeSnafu)?);
+            prev_tw.1 = Some(prev_upper);
+
+            let cur_upper = upper_bound.unwrap_or(
+                lower_bound
+                    .add_duration(std_window_size)
+                    .context(TimeSnafu)?,
+            );
+
+            if lower_bound
+                .sub(&prev_upper)
+                .map(|dist| dist <= window_size * Self::MERGE_DIST)
+                .unwrap_or(false)
+            {
+                prev_tw.1 = Some(cur_upper);
+            } else {
+                new_windows.insert(prev_tw.0, prev_tw.1);
+                *prev_tw = (lower_bound, Some(cur_upper));
+            }
+        }
+
+        if let Some(prev_tw) = prev_tw {
+            new_windows.insert(prev_tw.0, prev_tw.1);
+        }
+
+        self.windows = new_windows;
+
+        Ok(())
+    }
+}
+
+impl RecordingRuleState {
+    pub fn new(query_ctx: QueryContextRef, shutdown_rx: oneshot::Receiver<()>) -> Self {
+        Self {
+            query_ctx,
+            last_update_time: Instant::now(),
+            last_query_duration: Duration::from_secs(0),
+            dirty_time_windows: Default::default(),
+            exec_state: ExecState::Idle,
+            shutdown_rx,
+        }
+    }
+
+    /// called after last query is done
+    /// `is_succ` indicate whether the last query is successful
+    pub fn after_query_exec(&mut self, elapsed: Duration, _is_succ: bool) {
+        self.exec_state = ExecState::Idle;
+        self.last_query_duration = elapsed;
+        self.last_update_time = Instant::now();
+    }
+
+    /// wait for at least `last_query_duration`, at most `max_timeout` to start next query
+    pub fn get_next_start_query_time(&self, max_timeout: Option<Duration>) -> Instant {
+        let next_duration = max_timeout
+            .unwrap_or(self.last_query_duration)
+            .min(self.last_query_duration);
+        let next_duration = next_duration.max(MIN_REFRESH_DURATION);
+
+        self.last_update_time + next_duration
+    }
+}
+
+#[derive(Debug, Clone)]
+enum ExecState {
+    Idle,
+    Executing,
+}
+
+#[cfg(test)]
+mod test {
+    use pretty_assertions::assert_eq;
+
+    use super::*;
+
+    #[test]
+    fn test_merge_dirty_time_windows() {
+        let mut dirty = DirtyTimeWindows::default();
+        dirty.add_lower_bounds(
+            vec![
+                Timestamp::new_second(0),
+                Timestamp::new_second((1 + DirtyTimeWindows::MERGE_DIST as i64) * 5 * 60),
+            ]
+            .into_iter(),
+        );
+        dirty
+            .merge_dirty_time_windows(chrono::Duration::seconds(5 * 60), None)
+            .unwrap();
+        // just enough to merge
+        assert_eq!(
+            dirty.windows,
+            BTreeMap::from([(
+                Timestamp::new_second(0),
+                Some(Timestamp::new_second(
+                    (2 + DirtyTimeWindows::MERGE_DIST as i64) * 5 * 60
+                ))
+            )])
+        );
+
+        // separate time window
+        let mut dirty = DirtyTimeWindows::default();
+        dirty.add_lower_bounds(
+            vec![
+                Timestamp::new_second(0),
+                Timestamp::new_second((2 + DirtyTimeWindows::MERGE_DIST as i64) * 5 * 60),
+            ]
+            .into_iter(),
+        );
+        dirty
+            .merge_dirty_time_windows(chrono::Duration::seconds(5 * 60), None)
+            .unwrap();
+        // just enough to merge
+        assert_eq!(
+            BTreeMap::from([
+                (
+                    Timestamp::new_second(0),
+                    Some(Timestamp::new_second(5 * 60))
+                ),
+                (
+                    Timestamp::new_second((2 + DirtyTimeWindows::MERGE_DIST as i64) * 5 * 60),
+                    Some(Timestamp::new_second(
+                        (3 + DirtyTimeWindows::MERGE_DIST as i64) * 5 * 60
+                    ))
+                )
+            ]),
+            dirty.windows
+        );
+
+        // overlapping
+        let mut dirty = DirtyTimeWindows::default();
+        dirty.add_lower_bounds(
+            vec![
+                Timestamp::new_second(0),
+                Timestamp::new_second((DirtyTimeWindows::MERGE_DIST as i64) * 5 * 60),
+            ]
+            .into_iter(),
+        );
+        dirty
+            .merge_dirty_time_windows(chrono::Duration::seconds(5 * 60), None)
+            .unwrap();
+        // just enough to merge
+        assert_eq!(
+            BTreeMap::from([(
+                Timestamp::new_second(0),
+                Some(Timestamp::new_second(
+                    (1 + DirtyTimeWindows::MERGE_DIST as i64) * 5 * 60
+                ))
+            ),]),
+            dirty.windows
+        );
+
+        // expired
+        let mut dirty = DirtyTimeWindows::default();
+        dirty.add_lower_bounds(
+            vec![
+                Timestamp::new_second(0),
+                Timestamp::new_second((DirtyTimeWindows::MERGE_DIST as i64) * 5 * 60),
+            ]
+            .into_iter(),
+        );
+        dirty
+            .merge_dirty_time_windows(
+                chrono::Duration::seconds(5 * 60),
+                Some(Timestamp::new_second(
+                    (DirtyTimeWindows::MERGE_DIST as i64) * 6 * 60,
+                )),
+            )
+            .unwrap();
+        // just enough to merge
+        assert_eq!(BTreeMap::from([]), dirty.windows);
+    }
+}

src/flow/src/recording_rules/frontend_client.rs

@@ -0,0 +1,163 @@
+// 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.
+
+//! Frontend client to run flow as recording rule which is time-window-aware normal query triggered every tick set by user
+
+use std::sync::Arc;
+
+use client::{Client, Database, DEFAULT_CATALOG_NAME, DEFAULT_SCHEMA_NAME};
+use common_error::ext::BoxedError;
+use common_grpc::channel_manager::{ChannelConfig, ChannelManager};
+use common_meta::cluster::{NodeInfo, NodeInfoKey, Role};
+use common_meta::peer::Peer;
+use common_meta::rpc::store::RangeRequest;
+use meta_client::client::MetaClient;
+use snafu::ResultExt;
+
+use crate::error::{ExternalSnafu, UnexpectedSnafu};
+use crate::recording_rules::engine::DEFAULT_RULE_ENGINE_QUERY_TIMEOUT;
+use crate::Error;
+
+fn default_channel_mgr() -> ChannelManager {
+    let cfg = ChannelConfig::new().timeout(DEFAULT_RULE_ENGINE_QUERY_TIMEOUT);
+    ChannelManager::with_config(cfg)
+}
+
+fn client_from_urls(addrs: Vec<String>) -> Client {
+    Client::with_manager_and_urls(default_channel_mgr(), addrs)
+}
+
+/// A simple frontend client able to execute sql using grpc protocol
+#[derive(Debug)]
+pub enum FrontendClient {
+    Distributed {
+        meta_client: Arc<MetaClient>,
+        channel_mgr: ChannelManager,
+    },
+    Standalone {
+        /// for the sake of simplicity still use grpc even in standalone mode
+        /// notice the client here should all be lazy, so that can wait after frontend is booted then make conn
+        /// TODO(discord9): not use grpc under standalone mode
+        database_client: DatabaseWithPeer,
+    },
+}
+
+#[derive(Debug, Clone)]
+pub struct DatabaseWithPeer {
+    pub database: Database,
+    pub peer: Peer,
+}
+
+impl DatabaseWithPeer {
+    fn new(database: Database, peer: Peer) -> Self {
+        Self { database, peer }
+    }
+}
+
+impl FrontendClient {
+    pub fn from_meta_client(meta_client: Arc<MetaClient>) -> Self {
+        Self::Distributed {
+            meta_client,
+            channel_mgr: default_channel_mgr(),
+        }
+    }
+
+    pub fn from_static_grpc_addr(addr: String) -> Self {
+        let peer = Peer {
+            id: 0,
+            addr: addr.clone(),
+        };
+
+        let mgr = default_channel_mgr();
+        let client = Client::with_manager_and_urls(mgr.clone(), vec![addr]);
+        let database = Database::new(DEFAULT_CATALOG_NAME, DEFAULT_SCHEMA_NAME, client);
+        Self::Standalone {
+            database_client: DatabaseWithPeer::new(database, peer),
+        }
+    }
+}
+
+impl FrontendClient {
+    async fn scan_for_frontend(&self) -> Result<Vec<(NodeInfoKey, NodeInfo)>, Error> {
+        let Self::Distributed { meta_client, .. } = self else {
+            return Ok(vec![]);
+        };
+        let cluster_client = meta_client
+            .cluster_client()
+            .map_err(BoxedError::new)
+            .context(ExternalSnafu)?;
+        let cluster_id = meta_client.id().0;
+        let prefix = NodeInfoKey::key_prefix_with_role(cluster_id, Role::Frontend);
+        let req = RangeRequest::new().with_prefix(prefix);
+        let resp = cluster_client
+            .range(req)
+            .await
+            .map_err(BoxedError::new)
+            .context(ExternalSnafu)?;
+        let mut res = Vec::with_capacity(resp.kvs.len());
+        for kv in resp.kvs {
+            let key = NodeInfoKey::try_from(kv.key)
+                .map_err(BoxedError::new)
+                .context(ExternalSnafu)?;
+
+            let val = NodeInfo::try_from(kv.value)
+                .map_err(BoxedError::new)
+                .context(ExternalSnafu)?;
+            res.push((key, val));
+        }
+        Ok(res)
+    }
+
+    /// Get the database with max `last_activity_ts`
+    async fn get_last_active_frontend(&self) -> Result<DatabaseWithPeer, Error> {
+        if let Self::Standalone { database_client } = self {
+            return Ok(database_client.clone());
+        }
+        match &self {
+            Self::Standalone { database_client } => Ok(database_client.clone()),
+            Self::Distributed {
+                meta_client: _,
+                channel_mgr,
+            } => {
+                let frontends = self.scan_for_frontend().await?;
+                let mut last_activity_ts = i64::MIN;
+                let mut peer = None;
+                for (_key, val) in frontends.iter() {
+                    if val.last_activity_ts > last_activity_ts {
+                        last_activity_ts = val.last_activity_ts;
+                        peer = Some(val.peer.clone());
+                    }
+                }
+                let Some(peer) = peer else {
+                    UnexpectedSnafu {
+                        reason: format!("No frontend available: {:?}", frontends),
+                    }
+                    .fail()?
+                };
+                let client =
+                    Client::with_manager_and_urls(channel_mgr.clone(), vec![peer.addr.clone()]);
+                let database = Database::new(DEFAULT_CATALOG_NAME, DEFAULT_SCHEMA_NAME, client);
+                Ok(DatabaseWithPeer::new(database, peer))
+            }
+        }
+    }
+
+    /// Get a database client, and possibly update it before returning.
+    pub async fn get_database_client(&self) -> Result<DatabaseWithPeer, Error> {
+        match self {
+            Self::Standalone { database_client } => Ok(database_client.clone()),
+            Self::Distributed { meta_client: _, .. } => self.get_last_active_frontend().await,
+        }
+    }
+}

src/flow/src/server.rs

@@ -57,6 +57,7 @@ use crate::error::{
 };
 use crate::heartbeat::HeartbeatTask;
 use crate::metrics::{METRIC_FLOW_PROCESSING_TIME, METRIC_FLOW_ROWS};
+use crate::recording_rules::{FrontendClient, RecordingRuleEngine};
 use crate::transform::register_function_to_query_engine;
 use crate::utils::{SizeReportSender, StateReportHandler};
 use crate::{Error, FlowWorkerManager, FlownodeOptions};
@@ -245,6 +246,7 @@ impl FlownodeInstance {
         self.server.shutdown().await.context(ShutdownServerSnafu)?;
 
         if let Some(task) = &self.heartbeat_task {
+            info!("Close heartbeat task for flownode");
             task.shutdown();
         }
 
@@ -271,6 +273,8 @@ pub struct FlownodeBuilder {
     heartbeat_task: Option<HeartbeatTask>,
     /// receive a oneshot sender to send state size report
     state_report_handler: Option<StateReportHandler>,
+    /// Client to send sql to frontend
+    frontend_client: Arc<FrontendClient>,
 }
 
 impl FlownodeBuilder {
@@ -281,6 +285,7 @@ impl FlownodeBuilder {
         table_meta: TableMetadataManagerRef,
         catalog_manager: CatalogManagerRef,
         flow_metadata_manager: FlowMetadataManagerRef,
+        frontend_client: Arc<FrontendClient>,
     ) -> Self {
         Self {
             opts,
@@ -290,6 +295,7 @@ impl FlownodeBuilder {
             flow_metadata_manager,
             heartbeat_task: None,
             state_report_handler: None,
+            frontend_client,
         }
     }
 
@@ -447,7 +453,14 @@ impl FlownodeBuilder {
 
         let node_id = self.opts.node_id.map(|id| id as u32);
 
-        let mut man = FlowWorkerManager::new(node_id, query_engine, table_meta);
+        let rule_engine = RecordingRuleEngine::new(
+            self.frontend_client.clone(),
+            query_engine.clone(),
+            self.flow_metadata_manager.clone(),
+            table_meta.clone(),
+        );
+
+        let mut man = FlowWorkerManager::new(node_id, query_engine, table_meta, rule_engine);
         for worker_id in 0..num_workers {
             let (tx, rx) = oneshot::channel();
 

src/flow/src/test_utils.rs

@@ -86,7 +86,8 @@ pub fn create_test_query_engine() -> Arc<dyn QueryEngine> {
 
     let schema = vec![
         datatypes::schema::ColumnSchema::new("number", CDT::uint32_datatype(), false),
-        datatypes::schema::ColumnSchema::new("ts", CDT::timestamp_millisecond_datatype(), false),
+        datatypes::schema::ColumnSchema::new("ts", CDT::timestamp_millisecond_datatype(), false)
+            .with_time_index(true),
     ];
     let mut columns = vec![];
     let numbers = (1..=10).collect_vec();
@@ -114,6 +115,37 @@ pub fn create_test_query_engine() -> Arc<dyn QueryEngine> {
     };
     catalog_list.register_table_sync(req_with_ts).unwrap();
 
+    let schema = vec![
+        datatypes::schema::ColumnSchema::new("NUMBER", CDT::uint32_datatype(), false),
+        datatypes::schema::ColumnSchema::new("ts", CDT::timestamp_millisecond_datatype(), false)
+            .with_time_index(true),
+    ];
+    let mut columns = vec![];
+    let numbers = (1..=10).collect_vec();
+    let column: VectorRef = Arc::new(<u32 as Scalar>::VectorType::from_vec(numbers));
+    columns.push(column);
+
+    let ts = (1..=10).collect_vec();
+    let mut builder = TimestampMillisecondVectorBuilder::with_capacity(10);
+    ts.into_iter()
+        .map(|v| builder.push(Some(TimestampMillisecond::new(v))))
+        .count();
+    let column: VectorRef = builder.to_vector_cloned();
+    columns.push(column);
+
+    let schema = Arc::new(Schema::new(schema));
+    let recordbatch = common_recordbatch::RecordBatch::new(schema, columns).unwrap();
+    let table = MemTable::table("UPPERCASE_NUMBERS_WITH_TS", recordbatch);
+
+    let req_with_ts = RegisterTableRequest {
+        catalog: DEFAULT_CATALOG_NAME.to_string(),
+        schema: DEFAULT_SCHEMA_NAME.to_string(),
+        table_name: "UPPERCASE_NUMBERS_WITH_TS".to_string(),
+        table_id: 1025,
+        table,
+    };
+    catalog_list.register_table_sync(req_with_ts).unwrap();
+
     let factory = query::QueryEngineFactory::new(catalog_list, None, None, None, None, false);
 
     let engine = factory.query_engine();

src/meta-client/src/client.rs

@@ -112,6 +112,7 @@ impl MetaClientBuilder {
             .enable_store()
             .enable_heartbeat()
             .enable_procedure()
+            .enable_access_cluster_info()
     }
 
     pub fn enable_heartbeat(self) -> Self {

src/meta-srv/Cargo.toml

@@ -7,6 +7,7 @@ license.workspace = true
 [features]
 mock = []
 pg_kvbackend = ["dep:tokio-postgres", "common-meta/pg_kvbackend"]
+mysql_kvbackend = []                                              # placeholder features so CI can compile
 
 [lints]
 workspace = true

src/operator/src/insert.rs

@@ -68,6 +68,7 @@ pub struct Inserter {
     catalog_manager: CatalogManagerRef,
     partition_manager: PartitionRuleManagerRef,
     node_manager: NodeManagerRef,
+    #[allow(unused)]
     table_flownode_set_cache: TableFlownodeSetCacheRef,
 }
 
@@ -338,6 +339,8 @@ impl Inserter {
             instant_requests,
         } = requests;
 
+        // TODO(discord9): mirror some
+
         // Mirror requests for source table to flownode asynchronously
         let flow_mirror_task = FlowMirrorTask::new(
             &self.table_flownode_set_cache,
@@ -817,12 +820,14 @@ struct CreateAlterTableResult {
     table_infos: HashMap<TableId, Arc<TableInfo>>,
 }
 
+#[allow(unused)]
 struct FlowMirrorTask {
     requests: HashMap<Peer, RegionInsertRequests>,
     num_rows: usize,
 }
 
 impl FlowMirrorTask {
+    #[allow(unused)]
     async fn new(
         cache: &TableFlownodeSetCacheRef,
         requests: impl Iterator<Item = &RegionInsertRequest>,
@@ -896,6 +901,7 @@ impl FlowMirrorTask {
         })
     }
 
+    #[allow(unused)]
     fn detach(self, node_manager: NodeManagerRef) -> Result<()> {
         crate::metrics::DIST_MIRROR_PENDING_ROW_COUNT.add(self.num_rows as i64);
         for (peer, inserts) in self.requests {

tests-integration/src/standalone.rs

@@ -40,7 +40,7 @@ use common_procedure::options::ProcedureConfig;
 use common_procedure::ProcedureManagerRef;
 use common_wal::config::{DatanodeWalConfig, MetasrvWalConfig};
 use datanode::datanode::DatanodeBuilder;
-use flow::FlownodeBuilder;
+use flow::{FlownodeBuilder, FrontendClient};
 use frontend::instance::builder::FrontendBuilder;
 use frontend::instance::{FrontendInstance, Instance, StandaloneDatanodeManager};
 use meta_srv::metasrv::{FLOW_ID_SEQ, TABLE_ID_SEQ};
@@ -164,12 +164,15 @@ impl GreptimeDbStandaloneBuilder {
             Some(procedure_manager.clone()),
         );
 
+        let fe_server_addr = opts.frontend_options().grpc.bind_addr.clone();
+        let frontend_client = FrontendClient::from_static_grpc_addr(fe_server_addr);
         let flow_builder = FlownodeBuilder::new(
             Default::default(),
             plugins.clone(),
             table_metadata_manager.clone(),
             catalog_manager.clone(),
             flow_metadata_manager.clone(),
+            Arc::new(frontend_client),
         );
         let flownode = Arc::new(flow_builder.build().await.unwrap());