Summary

Together with our global community of contributors, GreptimeDB continues to evolve and flourish as a growing open-source project. We are grateful to each and every one of you.

Below are the highlights among recent commits:

• Implements Bulk MemTable, speedup large batch write request
• New SELECT processor for Pipeline

Contributors

For the past two weeks, our community has been super active with a total of 76 PRs merged. 2 PRs from 2 individual contributors merged successfully and lots pending to be merged.

Congrats on becoming our most active contributors in the past 2 weeks:

• @omahs db#6084
• @zqr10159 docs#1722

👏 Welcome @omahs @zqr10159 to the community as a new contributor with a successfully merged PR, and more PRs from other individual contributors are waiting to be merged.

（Figure 1: New Individual Contributors）

A big THANK YOU to all our members and contributors! It is people like you who are making GreptimeDB a great product. Let's build an even greater community together.

Highlights of Recent PRs

db#6054 Implements Bulk MemTable

Introduce Bulk MemTable, significantly improve write speed for write requests comes in large batch. For now, this feature will only be enabled for tables that don't have a primary key.

db#5939 Add format support for PromQL HTTP API

Add support for dump query result in different format using PromQL HTTP API, useful for user who need to handle query results in formats other than json, currently support formats are: arrow, csv, influxdb_v1, greptimedb_v1 and json. i.e:

> curl "localhost:4000/v1/promql?query=1&start=0&end=15&step=5s&format=csv"
0,1.0
5000,1.0
10000,1.0
15000,1.0

db#6019 New SELECT processor for Pipeline

Add a new select processor to include or exclude elements in the pipeline context during the process. i.e. This pipeline's SELECT processor select two column(ts and http_status_code) from four columns ts, http_status_code, content and message:

processors:
  - dissect:
      fields:
        - message
      patterns:
        - "%{+ts} %{+ts} %{http_status_code} %{content}"
  - date:
      fields:
        - ts
      formats:
        - "%Y-%m-%d %H:%M:%S%.3f"
  - select:
      fields:
        - ts
        - http_status_code

db#6073 Built-in Memory Profiler can generate flamegraph directly

The built-in memory profiler now support directly output flamegraph using HTTP API, helpful for profiling memory usage. i.e.(on linux):

# start the db with profiler on
MALLOC_CONF=prof:true greptime standalone start
# dump the flamegraph
curl -X POST "localhost:4000/debug/prof/mem?output=flamegraph" > greptime.svg

（Figure 2: The Example of Flamegraph）

Good First Issue

Issue#6067 Supports CSVWithNames and CSVWithNamesAndTypes formats

We currently support rendering SQL and PromQL results in CSV format, as detailed in CSV result format and its implementation in the /sql API.

However, the current csv output only includes rows, lacking column names and types.

ClickHouse's CSVWithNames and CSVWithNamesAndTypes formats, which include column names as headers and both names and types respectively, would greatly improve usability. These additions would facilitate easier data import and analysis in tools like Excel. Therefore, supporting these formats would be beneficial.

Difficulty: Simple

Keywords: SQL, Query, CSV

Issue#6068 Support SET DEFAULT/DROP DEFAULT

Support ALTER TABLE <table-name> ALTER COLUMN <column-name> SET DEFAULT <default-value>/DROP DEFAULT which sets a new default for a column or removes any default value.

Difficulty: Medium

Keywords: Alter table, Default value

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About Greptime

GreptimeDB is an open-source, cloud-native database purpose-built for real-time observability. Built in Rust and optimized for cloud-native environments, it provides unified storage and processing for metrics, logs, and traces—delivering sub-second insights from edge to cloud —at any scale.

• GreptimeDB OSS – The open-sourced database for small to medium-scale observability and IoT use cases, ideal for personal projects or dev/test environments.

• GreptimeDB Enterprise – A robust observability database with enhanced security, high availability, and enterprise-grade support.

• GreptimeCloud – A fully managed, serverless DBaaS with elastic scaling and zero operational overhead. Built for teams that need speed, flexibility, and ease of use out of the box.

🚀 We’re open to contributors—get started with issues labeled good first issue and connect with our community.

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