2025 Changelog

ClickHouse release v25.7.5.34-stable (a031c88152d) FIXME as compared to v25.7.4.11-stable (69641539983)

Performance Improvement

• Backported in #85685: Improve parallel files processing with delta-kernel-rs backend. #85642 (Azat Khuzhin).

Improvement

• Backported in #85729: Added show_data_lake_catalogs_in_system_tables flag to manage adding data lake tables in system.tables resolves #85384. #85411 (Smita Kulkarni).

Bug Fix (user-visible misbehavior in an official stable release)

• Backported in #85759: Fixed parquet writer outputting incorrect statistics (min/max) for Decimal types. #83754 (Michael Kolupaev).
• Backported in #85796: Fix writing JSON paths with NULL values in RowBinary format. #83923 (Pavel Kruglov).
• Backported in #85883: Fix reading Variant column with lazy materialization. #84400 (Pavel Kruglov).
• Backported in #85778: Fix race in DeltaLake engine delta-kernel implementation. #85221 (Kseniia Sumarokova).
• Backported in #85620: Queries with parallel replicas which uses reading reverse in order optimization can produce incorrect result. #85406 (Igor Nikonov).
• Backported in #85697: Fix possible UB (crashes) in case of MEMORY_LIMIT_EXCEEDED during String deserialization. #85440 (Azat Khuzhin).
• Backported in #85826: Fix incorrect metrics KafkaAssignedPartitions and KafkaConsumersWithAssignment. #85494 (Ilya Golshtein).
• Backported in #85916: Fix secrets masking in icebergS3Cluster and icebergAzureCluster table functions. #85658 (MikhailBurdukov).
• Backported in #85871: Fix coalescing merge tree segfault for large strings. This closes #84582. #85709 (Konstantin Vedernikov).
• Backported in #85854: Fix possible inconsistency for dictionaries with update_field on MEMORY_LIMIT_EXCEEDED errors. #85807 (Azat Khuzhin).
• Backported in #85993: Support global constants from WITH statement for the parallel distributed INSERT SELECT with the Distributed destination table. Before, the query could throw an Unknown expression identifier error. #85811 (Nikolai Kochetov).
• Backported in #86041: Fixed a bug in Replicated database recovery: if a table name contains the % symbol, it could re-create the table with a different name during recovery. #85987 (Alexander Tokmakov).

NOT FOR CHANGELOG / INSIGNIFICANT

• Backported in #85607: Sync read if content is in page cache. #85405 (Antonio Andelic).
• Backported in #85833: Add compatibility setting to write Date as UInt16 to parquet files. #85510 (Michael Kolupaev).