clickhouse
https://github.com/yandex/clickhouse
C++
ClickHouse is a free analytic DBMS for big data.
Triage Issues!
When you volunteer to triage issues, you'll receive an email each day with a link to an open issue that needs help in this project. You'll also receive instructions on how to triage issues.
Triage Docs!
Receive a documented method or class from your favorite GitHub repos in your inbox every day. If you're really pro, receive undocumented methods or classes and supercharge your commit history.
C++ not yet supported66 Subscribers
Add a CodeTriage badge to clickhouse
Help out
- Issues
- `Dynamic`: `NULL` after an expression row in `VALUES` stored as `'NULL'`/`0`
- Iceberg bucket split improvements
- clickhouse-client fails queries that set only one native binary-type flag
- Parquet over many local files: a second pool of decode threads competes with the reading streams; decoding in the reading threads makes short ClickBench queries 5-10% faster
- Support data skipping indices in projections
- Experiment: BOLT release builds with a weekly profile from benchmarks
- Use primary-key proofs to skip filter column reads in aggregations
- Parquet: String columns grow one row at a time while decoding dictionary runs and PLAIN pages; sizing them once makes ClickBench q11/q12/q26 13-22% faster
- Parallel parsing starts threads for small text files that fit in one segment; parse the first segment in the reading thread
- Parquet files read with pread: a cold range is read one read-ahead window at a time; advising the whole range first, in 128 KiB pieces, makes cold scans over 100 files 19-23% faster
- Docs
- C++ not yet supported