Weekly update in TiDB

Last week, we landed 40 PRs in the TiDB repository.

Added

• Add a failpoint switch to control expression pushdown in the integration test
• Add the SplitTable syntax to split table Regions
• Allow using SHARD_ROW_ID_BITS for tables with auto-increment columns

Improved

• Support loading statistics when the statistics lease is 0
• Disallow adding stored generated columns using ALTER TABLE
• Adjust the datum type when using the index query feedback
• Set SyncerSessionTTL to a smaller value
• Add a blacklist to disallow pushing down specific expressions
• Propagate more possible props to enlarge search space in the planner
• Support resolving specified lock keys

Fixed

• Fix the create table like operation for partitioned tables
• Fix an issue about split table by
• Fix the wrong selectivity for the inner selection in index join
• Fix the behavior when the output of date_sub is of the Time type
• Fix some unnecessary loops in failures of running a range
• Exclude keys that are already locked in LockKeys
• Fix the issue that the backoff retry stops early

Weekly update in TiSpark

Last week, we landed 9 PRs in the TiSpark repository.

Fixed

• Fix a potential empty collection issue during Region pre-splitting

Improved

• Add the TiDB/TiKV/PD/Spark version supported for each latest major release

Weekly update in TiKV and PD

Last week, we landed 37 PRs in the TiKV and PD repositories.

Added

• Add blob-run-mode for Titan
• Pessimistic-txn
  • Resolve all optimistic locks when a non-pessimistic lock conflict occurs
  • Add metrics
  • Implement pessimistic rollback
• Implement the LIKE RPN Function
• Add metrics for Titan
• Use a different timeout for HTTP clients
• Add two metrics for gc_worker

Improved

• Reduce allocations in slow hash aggregation
• Check the iter status when scanning
• Improve bad_regions and tombstone subcommands for tikv-ctl
• Always merge left Regions into right ones
• Use spin::Mutex
• Use static metrics to reduce the cost of with_label_values
• Avoid useless calculation and WakeUp messages
• Expire long remaining detection information in DetectTable to prevent memory leak
• Disable the label check by default

Fixed

• Acquire the write lock for the write command

New contributors (Thanks!)

• tispark: windtalker
• tikv: xiamengyu
• tidb-operator: tkanng
• pd: b41sh
• docs-cn: tangenta