v5.3.3 is a patch release: there is no release note for this version.

v6.1.1 is a patch release. Key changes include:

• Make the SHOW DATABASES LIKE … statement case-insensitive #34766 @e1ijah1;
• Change the default value of tidb_enable_outer_join_reorder from 1 to 0, which disables Join Reorder's support for Outer Join by default..

v6.2.0 is a minor release. Key changes include:

• Support the SHOW COUNT() WARNINGS and SHOW COUNT() ERRORS statements #25068 @likzn;
• Add validation check for some system variables #35048 @morgo.

v5.4.2 is a patch release. Key changes include:

• Avoid sending requests to unhealthy TiKV nodes to improve availability #34906;
• Fix the issue of wrong TableDual plans cached in binary protocol #34690 #34678.

v5.3.2 is a patch release. Key changes include:

• Fix the issue that the REPLACE statement incorrectly changes other rows when the auto ID is out of range #29483;
• Fix the issue that Amazon S3 cannot correctly calculate the size of compressed data #30534.

v6.1.0 is a minor release. Key changes include:

• Improve the performance of the UnionScanRead operator #32433;
• Improve the display of task types in the output of EXPLAIN (add the MPP task type) #33332.

v5.4.1 is a patch release. Key changes include:

• Support using the PointGet plan for queries that read the _tidb_rowid column #31543;
• Add more logs and metrics for the Apply operator to show whether it is parallel #33887.

v5.2.4 is a patch release: there is no release note for this version.

v6.0.0 is a major release. Key changes include:

• Clear the placement rule settings of a table automatically after restoring the table using the FLASHBACK or RECOVER statement #31668;
• Add a performance overview dashboard to show core performance metrics on typical critical paths, making metrics analysis on TiDB easier #31676.

v6.0.0-alpha is a pre-release release. See full release notes for details.

v5.3.1 is a patch release. Key changes include:

• Change the default value of the system variable tidb_analyze_version from 2 to 1 #31748;
• Since v5.1.4, if TiKV is configured with storage.enable-ttl = true, the requests from TiDB are rejected, because the TTL feature of TiKV only supports the RawK….

v5.1.4 is a patch release. Key changes include:

• Change the default value of the system variable tidb_analyze_version from 2 to 1 #31748;
• Since v5.1.4, if TiKV is configured with storage.enable-ttl = true, the requests from TiDB are rejected, because the TTL feature of TiKV only supports the RawK….

v5.4.0 is a minor release. Key changes include:

• Add a new system variable tidb_enable_paging to determine whether to use paging to send Coprocessor requests. Enabling this feature can reduce the amount of da…;
• Support the ADMIN {SESSION | INSTANCE | GLOBAL} PLAN_CACHE syntax to clear the cached query plan #30370.

v5.3.3 is a patch release: there is no release note for this version.

v6.1.1 is a patch release. Key changes include:

• Make the SHOW DATABASES LIKE … statement case-insensitive #34766 @e1ijah1;
• Change the default value of tidb_enable_outer_join_reorder from 1 to 0, which disables Join Reorder's support for Outer Join by default..

v6.2.0 is a minor release. Key changes include:

• Support the SHOW COUNT() WARNINGS and SHOW COUNT() ERRORS statements #25068 @likzn;
• Add validation check for some system variables #35048 @morgo.

v5.4.2 is a patch release. Key changes include:

• Avoid sending requests to unhealthy TiKV nodes to improve availability #34906;
• Fix the issue of wrong TableDual plans cached in binary protocol #34690 #34678.

v5.3.2 is a patch release. Key changes include:

• Fix the issue that the REPLACE statement incorrectly changes other rows when the auto ID is out of range #29483;
• Fix the issue that Amazon S3 cannot correctly calculate the size of compressed data #30534.

v6.1.0 is a minor release. Key changes include:

• Improve the performance of the UnionScanRead operator #32433;
• Improve the display of task types in the output of EXPLAIN (add the MPP task type) #33332.

v5.4.1 is a patch release. Key changes include:

• Support using the PointGet plan for queries that read the _tidb_rowid column #31543;
• Add more logs and metrics for the Apply operator to show whether it is parallel #33887.

v5.2.4 is a patch release: there is no release note for this version.

v6.0.0 is a major release. Key changes include:

• Clear the placement rule settings of a table automatically after restoring the table using the FLASHBACK or RECOVER statement #31668;
• Add a performance overview dashboard to show core performance metrics on typical critical paths, making metrics analysis on TiDB easier #31676.

v6.0.0-alpha is a pre-release release. See full release notes for details.

v5.3.1 is a patch release. Key changes include:

• Change the default value of the system variable tidb_analyze_version from 2 to 1 #31748;
• Since v5.1.4, if TiKV is configured with storage.enable-ttl = true, the requests from TiDB are rejected, because the TTL feature of TiKV only supports the RawK….

v5.1.4 is a patch release. Key changes include:

• Change the default value of the system variable tidb_analyze_version from 2 to 1 #31748;
• Since v5.1.4, if TiKV is configured with storage.enable-ttl = true, the requests from TiDB are rejected, because the TTL feature of TiKV only supports the RawK….

v5.4.0 is a minor release. Key changes include:

• Add a new system variable tidb_enable_paging to determine whether to use paging to send Coprocessor requests. Enabling this feature can reduce the amount of da…;
• Support the ADMIN {SESSION | INSTANCE | GLOBAL} PLAN_CACHE syntax to clear the cached query plan #30370.