2026 Changelog

ClickHouse release v26.1.2.11-stable (53779390caa) FIXME as compared to v26.1.1.912-stable (4c47e680f55)

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

• Backported in #95646: Fix incorrect primary key and skip index pruning for predicates involving toWeek, toYearWeek, toStartOfWeek, toLastDayOfWeek, and toDayOfWeek, and fix exceptions in some of these functions for valid queries with LowCardinality(String). #94816 (Nihal Z. Miaji).
• Backported in #95634: Fixes a crash during ReplicatedMergeTree startup caused by concurrent removal of delete_tmp_* directories. #94892 (myeongjun).
• Backported in #95429: Make column transform only once during getting content of manifesrt .avro list and files. #95164 (Daniil Ivanik).
• Backported in #95620: Fix the prewhere filter error caused by lambda expressions in prewhere. #95395 (Xiaozhe Yu).
• Backported in #95610: Avoid possible crash for distributed queries in case of cancellation. #95466 (Aleksandr Musorin).
• Backported in #95699: Fixed There was an error: Cannot obtain error message logical error when waiting for a distributed DDL and dropping the Replicated database concurrently. Fixes #95539. #95664 (Alexander Tokmakov).

Build/Testing/Packaging Improvement

• Backported in #95416: Use OpenSSL 3.5.5. #95345 (Konstantin Bogdanov).

NOT FOR CHANGELOG / INSIGNIFICANT

• Backported in #95592: Fix MSan error in ColumnNullable::getSerializedValueSize (unreleased). #95342 (Alexey Milovidov).
• Backported in #95655: PR: adding parallel_replicas_filter_pushdown setting. #95510 (Igor Nikonov).
• Backported in #95586: Fix path traversal vulnerability in ATTACH PART FROM (unreleased). #95568 (Alexey Milovidov).