discord9 984f80e277 fix(query): stop windowed sort on precision-lowering time casts (#9524)
* test: cover windowed sort cast unit mismatch

Signed-off-by: discord9 <55937128+discord9@users.noreply.github.com>

* fix(query): stop windowed sort on unit- or timezone-changing time casts

A cast on the time index column keeps the windowed-sort optimization
eligible only when it preserves the underlying timestamp values. Casts
that change the time unit (e.g. ms -> s) or that add a timezone to a
naive timestamp re-interpret the values, so the working ranges derived
from the time index no longer describe the sort column and the scan
fails with a working-range error or silently wrong order. Reject both
cast shapes so such queries fall back to the normal SortExec path.

The integration fixture uses two rows 1000 seconds apart so the cast
output stays distinct and the ordering assertions are not vacuous; the
descending arm gets its own expectation.

Signed-off-by: discord9 <55937128+discord9@users.noreply.github.com>

* fix(query): stop windowed sort on unit-changing timestamp wrappers

to_timestamp_seconds/millis/... cast their argument to their own unit
inside the function, so the hidden cast bypassed the explicit-cast guard
and kept the windowed-sort optimization eligible on a sort column whose
values no longer match the working ranges. The wrapper branch now applies
the same unit- and value-preserving predicate as the cast branch, with
the predicate extracted into preserves_timestamp_values and shared by
both.

The integration regression gains to_timestamp_seconds ASC/DESC arms and
a to_timestamp_millis value-preserving control; unit tests cover
unit-changing, tz-adding, and non-timestamp wrapper inputs.

Signed-off-by: discord9 <55937128+discord9@users.noreply.github.com>

* test: regen windowed sort sqlness after wrapper guard

The windowed_sort_nanos and windowed_sort_advance cases sort by
to_timestamp_nanos over a millisecond index and to_timestamp_millis over
a nanosecond index. Both wrappers change the time unit inside the
function, so the windowed-sort rule no longer applies and the plans
render a plain SortExec. Query results are unchanged; only the EXPLAIN
plan line differs. Regenerated by the sqlness runner.

Signed-off-by: discord9 <55937128+discord9@users.noreply.github.com>

* test(query): simplify windowed sort cast regressions

Signed-off-by: discord9 <55937128+discord9@users.noreply.github.com>

---------

Signed-off-by: discord9 <55937128+discord9@users.noreply.github.com>
2026-10-27 11:51:43 +00:00
2023-08-10 08:08:37 +00:00
2023-06-25 11:05:46 +08:00
2023-11-09 10:38:12 +00:00

GreptimeDB Logo

Metrics, logs, and traces.
One engine, on your infrastructure.

A columnar database for metrics, logs, and traces on object storage. Apache-2.0 licensed core.

User Guide  ·  API Docs  ·  Roadmap 2026  ·  Slack

Stable Canary Nightly Docker Pulls License

stable for production  ·  canary includes pre-releases  ·  nightly is a weekly snapshot of main

Introduction

GreptimeDB is an open-source observability database. Metrics, logs, and traces run on one columnar engine over object storage and share one table model: tags, timestamp, and fields. When signals carry common identifiers such as service, host, or trace ID, you can correlate them in SQL without moving data between databases.

Ingest through OpenTelemetry, Prometheus Remote Write, Loki Push, or Elasticsearch Bulk. Use SQL across observability data and PromQL for metrics. Migrate ingestion one signal at a time without rebuilding your collectors.

One Query Across Signals

OpenTelemetry ingestion writes spans to opentelemetry_traces and log records to opentelemetry_logs. Both tables carry trace_id, so correlating them is a join:

-- The slowest failed spans in the last hour,
-- with the log lines emitted inside those same traces.
SELECT
    t.service_name,
    t.span_name,
    t.duration_nano / 1000000 AS duration_ms,
    l.timestamp AS log_time,
    l.severity_text,
    l.body
FROM opentelemetry_traces t
JOIN opentelemetry_logs l ON l.trace_id = t.trace_id
WHERE t.timestamp > now() - INTERVAL '1' HOUR
  AND t.span_status_code = 'STATUS_CODE_ERROR'
ORDER BY t.duration_nano DESC
LIMIT 20;

Metrics join the same way, on any tag the tables share, such as service, host, or pod.

Why You Might Use It

  • You run Prometheus plus Loki or Elasticsearch and want one backend instead of three
  • You have outgrown Prometheus on cardinality or retention and don't want the Thanos/Mimir operational surface
  • You are hitting Loki's query performance limits as log volume grows
  • You need long retention on object storage without a separate analytics stack
  • You want to query telemetry with SQL, not only a domain query language
  • You are storing GenAI or agent telemetry (OTel GenAI conventions) alongside infrastructure signals

Learn more in Why GreptimeDB.

What's Supported

Ingest OpenTelemetry (OTLP), Prometheus Remote Write, Loki Push, Elasticsearch Bulk, InfluxDB line protocol, gRPC
Query SQL, PromQL, Jaeger-compatible trace queries, MySQL and PostgreSQL wire protocols
Storage S3, GCS, Azure Blob and S3-compatible endpoints as primary storage, with memory and local-disk caches
Built in Retention policies, downsampling, continuous aggregation, explicit table partitioning, and inverted / skipping / fulltext indexes

Compute and storage are disaggregated: object storage holds the data, while memory and local-disk caches keep recent and frequently queried data close to compute.

GreptimeDB Overview

Benchmarks

Compatibility and Migration

Compatibility is per protocol, and query-side coverage is narrower than ingestion.

Compatible Not compatible
Prometheus Remote Write ingestion; PromQL queries Gaps are listed in PromQL compatibility
Loki Push ingestion; dual-write through Grafana Alloy makes the cutover gradual LogQL and the rest of the Loki query API
Elasticsearch _bulk ingestion in the open-source core; QueryDSL partially, in Enterprise Most other Elasticsearch APIs

Limitations and Edition Boundary

Cluster deployment, object storage, the Flow engine, and every ingestion protocol listed above are in the Apache-2.0 build. Repartitioning, region migration, and index creation are manual operations there.

Read replicas, workload isolation, and automated repartitioning are GreptimeDB Enterprise features, along with enterprise security and governance. The Enterprise overview has the current list, and pricing has the edition comparison.

Architecture

GreptimeDB can run in two modes:

  • Standalone — single binary for development and small deployments.
  • Distributed — four components, each independently scalable:
    • Frontend — protocol entry (OTel, Prometheus, MySQL/PostgreSQL, gRPC, ingestion APIs for Elasticsearch/InfluxDB/Loki) and the distributed query engine. Stateless, scales horizontally.
    • Datanode — region engine with WAL, memtable, SST, cache, compaction, and indexes. Persists data to object storage. Elastic.
    • Metasrv — metadata, routing, repartitioning, and security. Backed by a pluggable KV layer (etcd or RDS).
    • Flownode (optional) — continuous flow computation (streaming and materialized views).

For deeper coverage, see the architecture doc or DeepWiki.

GreptimeDB System Overview

Try GreptimeDB

For AI agents — paste this prompt into your agent:

Read https://docs.greptime.com/SKILL.md and follow the instructions
to deploy, configure, ingest, and query GreptimeDB.
docker run -p 127.0.0.1:4000-4003:4000-4003 \
  -v "$(pwd)/greptimedb_data:/greptimedb_data" \
  --name greptime --rm \
  greptime/greptimedb:latest standalone start \
  --http-addr 0.0.0.0:4000 \
  --grpc-bind-addr 0.0.0.0:4001 \
  --mysql-addr 0.0.0.0:4002 \
  --postgres-addr 0.0.0.0:4003

Dashboard: http://localhost:4000/dashboard

Read more in the full Install Guide.

Troubleshooting:

  • Cannot connect to the database? Ensure that ports 4000, 4001, 4002, and 4003 are not blocked by a firewall or used by other services.
  • Failed to start? Check the container logs with docker logs greptime for further details.

Getting Started

Build From Source

Prerequisites:

  • Rust toolchain — stable, pinned by rust-toolchain.toml
  • Protobuf compiler (>= 3.15)
  • C/C++ building essentials: gcc / g++ / autoconf and the glibc dev package (libc6-dev on Ubuntu, glibc-devel on Fedora)
  • Python toolchain (optional, only for some test scripts)

Build and run:

make                          # build greptime binary
cargo run -- standalone start # start in standalone mode

Common dev commands:

make fmt            # format Rust code
make clippy         # lint (fails on warnings)
make test           # unit + integration tests (uses cargo-nextest)
make sqlness-test   # SQL regression tests

See the Contribution Guidelines for the full developer workflow.

Tools & Extensions

Project Status

GreptimeDB is generally available, with stable APIs and regular releases. It runs in production at scale — OceanBase Cloud operates 80+ GreptimeDB clusters managing 300 TB of logs, cutting log storage cost by 60%+ after migrating from Grafana Loki. See more in case studies.

Release lines and support windows are in the version reference. For where the project is going, read the v1.0 highlights and the 2026 roadmap.

Community

We invite you to engage and contribute!

If GreptimeDB is useful to you, please star the repo.

Known Users

License

GreptimeDB is an open-core project. Its core is licensed under the Apache License 2.0.

A small set of peripheral, enterprise-only features are gated behind the enterprise Cargo feature (not built by default) and are governed by the separate GreptimeDB Enterprise License. Source files under that license carry an explicit Enterprise License header.

Commercial Support

Scaling observability on your infrastructure? GreptimeDB Enterprise adds the operational, security, and support layer for production deployments. Contact us for details.

Contributing

Integration CI Codecov

Acknowledgement

Special thanks to all contributors! See AUTHOR.md.


All trademarks, logos, and brand names referenced in this README and in the Overview diagram are the property of their respective owners. Their use is for identification purposes only and does not imply endorsement or affiliation.

S
Description
Open-source, cloud-native, unified observability database for metrics, logs and traces, supporting SQL/PromQL/Streaming.
Readme Apache-2.0
1.6 GiB
Languages
Rust 97.4%
Python 1.8%
Shell 0.4%
JavaScript 0.2%