TiDB 5.1.5 Release Notes

Release date: December 28, 2022

TiDB version: 5.1.5

Quick access: Quick start | Production deployment | Installation packages

Compatibility changes

• PD

  • Disable compiling swagger server by default #4932

Bug fixes

• TiDB

  • Fix the issue that the window function causes TiDB to panic instead of reporting an error #30326
  • Fix the wrong result that occurs when enabling dynamic mode in partitioned tables for TiFlash #37254
  • Fix wrong results of GREATEST and LEAST when passing in unsigned BIGINT arguments #30101
  • Fix wrong results of deleting data of multiple tables using left join #31321
  • Fix the issue that the result of concat(ifnull(time(3))) in TiDB is different from that in MySQL #29498
  • Fix the issue that the SQL statements that contain cast(integer as char) union string return wrong results #29513
  • Fix the issue that INL_HASH_JOIN might hang when used with LIMIT #35638
  • Fix the wrong ANY_VALUE result that occurs when a Region returns empty data #30923
  • Fix wrong results of index join caused by an innerWorker panic #31494
  • Fix the issue that a SQL operation is canceled when its JSON type column joins its CHAR type column #29401
  • Fix the issue that the background HTTP service of TiDB might not exit successfully and makes the cluster in an abnormal state #30571
  • Fix the issue that concurrent column type change causes inconsistency between the schema and the data #31048
  • Fix the issue that KILL TIDB cannot take effect immediately on idle connections #24031
  • Fix the bug that setting any session variable will make tidb_snapshot fail to work #35515
  • Fix the issue that the Region cache is not cleaned up in time when the Region is merged #37141
  • Fix the panic issue caused by the connection array race in the KV client #33773
  • Fix the issue that when TiDB Binlog is enabled, executing the ALTER SEQUENCE statement might cause a wrong metadata version and cause Drainer to exit #36276
  • Fix the bug that TiDB may panic when querying statement summary tables #35340
  • Fix the issue that TiDB gets the wrong result when using TiFlash to scan tables with empty range although TiFlash does not support reading tables with empty range yet #33083
  • Fix the issue that the avg() function returns ERROR 1105 (HY000): other error for mpp stream: Could not convert to the target type - -value is out of range. when queried from TiFlash #29952
  • Fix the issue that ERROR 1105 (HY000): close of nil channel is returned when using HashJoinExec #30289
  • Fix the issue that TiKV and TiFlash return different results when querying logical operations #37258
  • Fix the issue that the EXECUTE statement might throw an unexpected error in specific scenarios #37187
  • Fix the planner wrong behaviors that occur when tidb_opt_agg_push_down and tidb_enforce_mpp are enabled #34465
  • Fix a bug that TiDB might send coprocessor requests when executing the SHOW COLUMNS statement #36496
  • Add warnings for lock tables and unlock tables when the enable-table-lock flag is not enabled #28967
  • Fix the issue that range partitions allow multiple MAXVALUE partitions #36329

• TiKV

  • Fix the issue of time parsing error that occurs when the DATETIME values contain a fraction and Z #12739
  • Fix a bug that replica reads might violate the linearizability #12109
  • Fix a bug that Regions might be overlapped if Raftstore is busy #13160
  • Fix the TiKV panic issue that occurs when applying snapshot is aborted #11618
  • Fix a bug that TiKV might panic if it has been running for 2 years or more #11940
  • Fix the panic issue that might occur when the source peer catches up logs by snapshot in the Region merge process #12663
  • Fix the issue that TiKV panics when performing type conversion for an empty string #12673
  • Fix a bug that stale messages cause TiKV to panic #12023
  • Fix the panic issue that might occur when a peer is being split and destroyed at the same time #12825
  • Fix the TiKV panic issue that occurs when the target peer is replaced with the peer that is destroyed without being initialized when merging a Region #12048
  • Fix the issue that TiKV reports the invalid store ID 0 error when using Follower Read #12478
  • Fix the possible duplicate commit records in pessimistic transactions when async commit is enabled #12615
  • Support configuring the unreachable_backoff item to avoid Raftstore broadcasting too many messages after one peer becomes unreachable #13054
  • Fix the issue that successfully committed optimistic transactions may report the Write Conflict error when the network is poor #34066
  • Fix the wrong expression of Unified Read Pool CPU in dashboard #13086

• PD

  • Fix the issue that a removed tombstone store appears again after the PD leader transfer ​​#4941
  • Fix the issue that scheduling cannot start immediately after the PD leader transfer #4769
  • Fix the wrong status code of not leader #4797
  • Fix the issue that PD cannot correctly handle dashboard proxy requests #5321
  • Fix a bug of TSO fallback in some corner cases #4884
  • Fix the issue that the TiFlash learner replica might not be created in specific scenarios #5401
  • Fix the issue that the label distribution has residual labels in the metrics #4825
  • Fix the issue that when there exists a Store with large capacity (2T for example), fully allocated small Stores cannot be detected, which results in no balance operator being generated #4805
  • Fix the issue that schedulers do not work when SchedulerMaxWaitingOperator is set to 1 #4946

• TiFlash

  • Fix incorrect microsecond when casting string to datetime #3556
  • Fix the panic issue that occurs when TLS is enabled #4196
  • Fix a bug that TiFlash might crash due to an error in parallel aggregation #5356
  • Fix the issue that a query containing JOIN might be hung if an error occurs #4195
  • Fix the issue that the function OR returns wrong results #5849
  • Fix the bug that invalid storage directory configurations lead to unexpected behaviors #4093
  • Fix potential data inconsistency after a lot of INSERT and DELETE operations #4956
  • Fix a bug that data not matching any region range remains on a TiFlash node #4414
  • Fix the potential query error after adding columns under heavy read workload #3967
  • Fix repeated crashes caused by the commit state jump backward errors #2576
  • Fix potential errors when querying on a table with many delete operations #4747
  • Fix the issue that the date format identifies '' as an invalid separator #4036
  • Fix the wrong result that occurs when casting DATETIME to DECIMAL #4151
  • Fix the bug that some exceptions are not handled properly #4101
  • Fix the issue that Prepare Merge might damage the metadata of the raft store and cause TiFlash to restart #3435
  • Fix a bug that an MPP query might fail due to random gRPC keepalive timeout #4662
  • Fix the issue that the result of IN is incorrect in multi-value expressions #4016
  • Fix a bug that MPP tasks might leak threads forever #4238
  • Fix the issue that expired data is recycled slowly #4146
  • Fix the overflow that occurs when casting FLOAT to DECIMAL #3998
  • Fix the issue that logical operators return wrong results when the argument type is UInt8 #6127
  • Fix the potential index out of bounds error if calling json_length with empty string #2705
  • Fix wrong decimal comparison results in corner cases #4512
  • Fix TiFlash_schema_error reported when NOT NULL columns are added #4596
  • Fix the issue that TiFlash bootstrap fails when 0.0 is used as the default value for integers, for example, `i` int(11) NOT NULL DEFAULT '0.0' #3157

• Tools

  • TiDB Binlog

    • Fix the issue that Drainer cannot send requests to Pump correctly when compressor is set to zip #1152

  • Backup & Restore (BR)

    • Fix the issue that system tables cannot be restored because concurrently backing up system tables makes the table name fail to update #29710

  • TiCDC

    • Fix data loss that occurs in special incremental scanning scenarios #5468
    • Fix the issue that there are no sorter metrics #5690
    • Fix excessive memory usage by optimizing the way DDL schemas are buffered #1386