Altinity Stable for ClickHouse 20.3.19.4

Description

The release includes several dozen bug fixes from the previous release.

Major New Features

• Server startup time has been reduced by parsing metadata in parallel.
• Improved performance of primary key analysis for LowCardinality columns. That was a performance regression introduced in 20.3.
• Improved performance of queries with large tuples and tuples used in primary key.

Bug Fixes

• Fixed a bug that prevented attaching Materialized Views to system tables.
• Fixed incorrect behavior of if function with NULLs.
• Fixed segfaults in rare cases.
• Fixed a bug that prevented predicate pushdown for queries using WITH clause.
• Fixed SIGSEGV in Kafka engine when broker is unavailable.
• Fixed a bug leading to block structure mismatch error for queries with UNION and JOIN.
• Fixed TTL processing logic to process all partitions in one run.
• Fixed a bug of parsing of row policies from configuration files that could result in missing policies sometimes.
• Fixed a bug with ALTER TABLE UPDATE could produce incorrect results when updating Nullable columns.
• Fixed a bug with codecs not working properly for MergeTree compact parts.

References

Updated RPM packages for Altinity Stable Release can be found in the Altinity Stable Repository. The ClickHouse repository can be used for DEB packages but check version numbers carefully.