TiDB - v6.2.0

Improvements

• Support the SHOW COUNT(*) WARNINGS and SHOW COUNT(*) ERRORS statements #25068 @likzn
• Add validation check for some system variables #35048 @morgo
• Optimize the error messages for some type conversions #32447 @fanrenhoo
• The KILL command now supports DDL operations #24144 @morgo
• Make the output of SHOW TABLES/DATABASES LIKE … more MySQL-compatible. The column names in the output contain the LIKE value #35116 @likzn
• Improve the performance of JSON-related functions #35859 @wjhuang2016
• Improve the verification speed of password login using SHA-2 #35998 @virusdefender
• Simplify some log outputs #36011 @dveeden
• Optimize the Coprocessor communication protocol. This can greatly reduce the memory consumption of the TiDB processes when reading data, and further alleviate the OOM issue in the scenario of scanning tables and exporting data by Dumpling. The system variable tidb_enable_paging is introduced to control whether to enable this communication protocol (with the scope of SESSION or GLOBAL). This protocol is disabled by default. To enable it, set the variable value to true #35633 @tiancaiama @wshwsh12
• Optimize the accuracy of memory tracking for some operators (HashJoin, HashAgg, Update, Delete) (#35634, #35631, #35635 @wshwsh12) (#34096 @ekexium)
• The system table INFORMATION_SCHEMA.DATA_LOCK_WAIT supports recording the locking information of optimistic transactions #34609 @longfangson
• Add some monitoring metrics for transactions #34456 @longfangsong

Bug fixes

• Fix the issue that a partition is incorrectly pruned if a partition key is used in the query condition and the collate is different from the one in the query partition table #32749 @mjonss
• Fix the issue that SET ROLE cannot match the granted role if there are capital letters in the host #33061 @morgo
• Fix the issue that columns with auto_increment cannot be dropped #34891 @Defined2014
• Fix the issue that SHOW CONFIG shows some configuration items that have been removed #34867 @morgo
• Fix the issue that SHOW DATABASES LIKE … is case-sensitive #34766 @e11jah
• Fix the issue that SHOW TABLE STATUS LIKE ... is case-sensitive #7518 @likzn
• Fix the issue that max-index-length still reports an error in non-strict mode #34931 @e11jah
• Fix the issue that ALTER COLUMN ... DROP DEFAULT does not work #35018 @Defined2014
• Fix the issue that when you create a table, the default value and the type of a column are not consistent and are not automatically corrected #34881 @Lloyd-Pottiger
• Fix the issue that data in the mysql.columns_priv table is not deleted synchronously after you run DROP USER #35059 @lcwangchao
• Fix the issue of DDL jam by disallowing creating tables within the schemas of some systems #35205 @tangenta
• Fix the issue that querying partitioned tables might report "index-out-of-range" and "non used index" errors in some cases #35181 @mjonss
• Fix the issue that INTERVAL expr unit + expr might report an error #30253 @mjonss
• Fix a bug that a temporary table cannot be found after being created in a transaction #35644 @djshow832
• Fix the panic issue that occurs when setting collation to the ENUM column #31637 @wjhuang2016
• Fix the issue that when one PD node goes down, the query of information_schema.TIKV_REGION_STATUS fails due to not retrying other PD nodes #35708 @tangenta
• Fix the issue that SHOW CREATE TABLE … cannot correctly display set or ENUM columns after SET character_set_results = GBK #31338 @tangenta
• Fix the incorrect scope of the system variables tidb_log_file_max_days and tidb_config #35190 @morgo
• Fix the issue that the output of SHOW CREATE TABLE is not compatible with MySQL for the ENUM or SET column #36317 @Defined2014
• Fix the issue that when creating a table, the behavior of a LONG BYTE column is not compatible with MySQL #36239 @Defined2014
• Fix the issue that auto_increment = x does not take effect on temporary tables #36224 @djshow832
• Fix the wrong default value when modifying columns concurrently #35846 @wjhuang2016
• Avoid sending requests to unhealthy TiKV nodes to improve availability #34906 @sticnarf
• Fix the issue that the column list does not work in the LOAD DATA statement #35198 @SpadeA-Tang
• Fix the issue that in some scenarios the pessimistic lock is incorrectly added to the non-unique secondary index #36235 @ekexium