Releases

TiKV v8.5.6 brings column-level privileges, multi-dimensional slow query rules, shared locks for FK checks, and ~13 bug fixes including a memory leak in crossbeam skiplist and a rare pessimistic transaction data inconsistency.

• securityColumn-level privileges close a data isolation gap — audit your schemas

  TiDB now supports MySQL-compatible column-level GRANT/REVOKE. If you've been relying on view-based workarounds to restrict access to sensitive columns (PII, financial data), you can now enforce this at the privilege layer instead. Audit tables that contain sensitive columns and apply least-privilege grants. This also means existing privilege audits may be incomplete — review user grants against newly exposed column-level controls.

• breakingMigrate off Statistics Version 1 now — it's deprecated and removal is coming

  tidb_analyze_version=1 is deprecated in this release and will be removed in a future version. Run SHOW VARIABLES LIKE 'tidb_analyze_version' on all instances. If any are on v1, switch to v2 and re-run ANALYZE on affected tables. Version 2 produces more accurate histograms and is the only supported path going forward. Don't wait until the removal forces a rushed migration.

• enhancementEnable shared locks for FK checks to cut contention in write-heavy workloads

  If you run high-concurrency INSERT/UPDATE on child tables with foreign key constraints pointing to a small set of parent rows, you're likely hitting exclusive lock contention today. Set tidb_foreign_key_check_in_shared_lock=ON and benchmark — shared locks on the parent table allow concurrent FK checks without blocking each other. Test in staging first, as this changes locking semantics. Also pick up the fix for the pessimistic transaction prewrite retry inconsistency (issue #11187) — worth verifying your TiKV nodes are on this patch if you run pessimistic workloads.