v6.0.0-alpha: session: fix global sysdate_is_now won't work (#32785)

close pingcap/tidb#32784

tidb-server v5.3.1

Compatibility changes

• 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 RawKV mode #27303

Feature enhancements

• Support partition pruning for the built-in IN expression in Range partition tables #26739
• Improve the accuracy of tracking memory usage when IndexJoin is executed #28650

Bug fixes

• Fix a memory leak bug that occurs when the system variable tidb_analyze_version is set to 2 #32499
• Fix the issue that the MaxDays and MaxBackups configurations do not take effect for the slow log #25716
• Fix the issue that executing the INSERT ... SELECT ... ON DUPLICATE KEY UPDATE statement gets panic #28078
• Fix the wrong result that might occur when performing JOIN on ENUM type columns #27831
• Fix the issue that INDEX HASH JOIN returns the send on closed channel error #31129
• Fix the issue that using the BatchCommands API might block sending TiDB requests to TiKV in some rare cases #32500
• Fix the issue of potential data index inconsistency in optimistic transaction mode #30410
• Fix the issue that window functions might return different results when using a transaction or not #29947
• Fix the issue that the length information is wrong when casting Decimal to String #29417
• Fix the issue that the GREATEST function returns incorrect result that occurs when setting the tidb_enable_vectorized_expression vectorized expression to off #29434
• Fix the issue that the optimizer might cache invalid plans for join in some cases #28087
• Fix wrong results of the microsecond and hour functions in vectorized expressions #29244 #28643
• Fix the TiDB panic when executing the ALTER TABLE.. ADD INDEX statement in some cases #27687
• Fix a bug that the availability detection of MPP node does not work in some corner cases #3118
• Fix the DATA RACE issue when assigning MPP task ID #27952
• Fix the INDEX OUT OF RANGE error for a MPP query after deleting an empty dual table #28250
• Fix the issue of false positive error log invalid cop task execution summaries length for MPP queries #1791

tidb-server v5.1.4

Compatibility changes

• 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 RawKV mode #27303

Feature enhancements

• Support partition pruning for the built-in IN expression in Range partition tables #26739
• Improve the accuracy of tracking memory usage when IndexJoin is executed #28650

Bug fixes

• Fix a memory leak bug that occurs when the system variable tidb_analyze_version is set to 2 #32499
• Fix the issue that the MaxDays and MaxBackups configurations do not take effect for the slow log #25716
• Fix the issue that executing the INSERT ... SELECT ... ON DUPLICATE KEY UPDATE statement gets panic #28078
• Fix the wrong result that might occur when performing JOIN on ENUM type columns #27831
• Fix the issue that INDEX HASH JOIN returns the send on closed channel error #31129
• Fix the issue that using the BatchCommands API might block sending TiDB requests to TiKV in some rare cases #32500
• Fix the issue of potential data index inconsistency in optimistic transaction mode #30410
• Fix the issue that window functions might return different results when using a transaction or not #29947
• Fix the issue that the length information is wrong when casting Decimal to String #29417
• Fix the issue that the GREATEST function returns incorrect result that occurs when setting the tidb_enable_vectorized_expression vectorized expression to off #29434
• Fix the issue that the optimizer might cache invalid plans for join in some cases #28087
• Fix wrong results of the microsecond and hour functions in vectorized expressions #29244 #28643
• Fix the TiDB panic when executing the ALTER TABLE.. ADD INDEX statement in some cases #27687
• Fix a bug that the availability detection of MPP node does not work in some corner cases #3118
• Fix the DATA RACE issue when assigning MPP task ID #27952
• Fix the INDEX OUT OF RANGE error for a MPP query after deleting an empty dual table #28250
• Fix the issue of false positive error log invalid cop task execution summaries length for MPP queries #1791

tidb-server v5.4.0

Improvements

• 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 data to process and to reduce latency and resource consumption #30578
• Support the ADMIN {SESSION | INSTANCE | GLOBAL} PLAN_CACHE syntax to clear the cached query plan #30370

Bug fixes

• Fix the issue of the tidb_analyze_version value change that occurs when upgrading the cluster from v4.x to v5.x #25422
• Fix the issue of the wrong result that occurs when using different collations in a subquery #30748
• Fix the issue that the result of concat(ifnull(time(3)) in TiDB is different from that in MySQL #29498
• Fix the issue of potential data index inconsistency in optimistic transaction mode #30410
• Fix the issue that the query execution plan of IndexMerge is wrong when an expression cannot be pushed down to TiKV #30200
• Fix the issue that concurrent column type change causes inconsistency between the schema and the data #31048
• Fix the issue that the IndexMerge query result is wrong when there is a subquery #30913
• Fix the panic issue that occurs when the FetchSize is set too large in the client #30896
• Fix the issue that LEFT JOIN might be mistakenly converted to INNER JOIN #20510
• Fix the issue that panic might occur when the CASE-WHEN expression and collation are used together #30245
• Fix the issue of wrong query result that occurs when the IN value contains a binary constant #31261
• Fix the issue of wrong query result that occurs when CTE has a subquery #31255
• Fix the issue that executing the INSERT ... SELECT ... ON DUPLICATE KEY UPDATE statement gets panic #28078
• Fix the issue that INDEX HASH JOIN returns the send on closed channel error #31129

tidb-server v5.0.6

Bug fixes

• Fix the panic that might occur when DML and DDL statements are executed concurrently #30940
• Fix the TiDB panic when executing the ALTER TABLE.. ADD INDEX statement in some cases #27687
• Fix the issue that the enforce-mpp configuration does not take effect in v5.0.4 #29252
• Fix the TiDB panic when inserting invalid date values concurrently #25393
• Fix the unexpected can not found column in Schema column error for queries in the MPP mode #30980
• Fix the unexpected index out of range error when the planner is doing join reorder #24095
• Fix the wrong result of CONCAT(IFNULL(TIME(3)) #29498
• Fix wrong results of GREATEST and LEAST when passing in unsigned BIGINT arguments #30101
• Fix the issue that a SQL operation is canceled when its JSON type column joins its CHAR type column #29401
• Fix the data inconsistency issue caused by incorrect usage of lazy existence check and untouched key optimization #30410
• Fix the issue that window functions might return different results when using a transaction or not #29947
• Fix the issue that the SQL statements that contain cast(integer as char) union string return wrong results #29513
• Fix the issue that the Column 'col_name' in field list is ambiguous error is reported unexpectedly when a SQL statement contains natural join #25041
• Fix the issue that the index out of range [1] with length 1 error is reported when a SQL statement evaluates an aggregation result on the result of join in some cases #1978

tidb-server v4.0.16

Improvements

• Upgrade the Grafana version from 7.5.7 to 7.5.11

Bug fixes

• Fix the query panic caused by overflow in the statistics module when converting a range to points for cost estimation #23625
• Fix wrong results of the control functions (such as IF and CASE WHEN) when using the ENUM type data as parameters of such functions #23114
• Fix the issue that the GREATEST function returns inconsistent results due to different values of tidb_enable_vectorized_expression (on or off) #29434
• Fix the panic when applying index join on prefix indexes in some cases #24547
• Fix the issue that planner might cache invalid plans for join in some cases #28087
• Fix a bug that TiDB cannot insert null into a non-null column when sql_mode is empty #11648
• Fix the wrong result type of the GREATEST and LEAST functions #29019
• Fix the privilege check fail error when performing the grant and revoke operations to grant and revoke global level privileges #29675
• Fix the panic when using the CASE WHEN function on the ENUM data type #29357
• Fix wrong results of the microsecond function in vectorized expressions #29244
• Fix wrong results of the hour function in vectorized expression #28643
• Fix the issue that optimistic transaction conflicts might cause transactions to block each other #11148
• Fix the issue of incomplete log information from the auto analyze result #29188
• Fix the issue that using an invalid default date does not report an error when the SQL_MODE is 'NO_ZERO_IN_DATE' #26766
• Fix the issue that the Coprocessor Cache panel in Grafana does not display metrics. Now, Grafana displays the number of hits/miss/evict #26338
• Fix the issue that concurrently truncating the same partition causes DDL statements to stuck #26229
• Fix the issue that when the CONCAT function has a negative float type argument, the last digit of the argument number is chopped in the result #29417
• Fix the issue of an extra column in the query result when NATURAL JOIN is used to join multiple tables #29481
• Fix the issue that TopN is wrongly pushed down to indexPlan when IndexScan uses a prefix index #29711
• Fix the issue that retrying transactions with the auto-increment columns of DOUBLE type causes data corruption #29892

tidb-server v5.3.0

Improvements

• Show the affected SQL statements in the debug log when the coprocessor encounters a lock, which is helpful in diagnosing problems #27718
• Support showing the size of the backup and restore data when backing up and restoring data in the SQL logical layer #27247
• Improve the default collection logic of ANALYZE when tidb_analyze_version is 2, which accelerates collection and reduces resource overhead
• Introduce the ANALYZE TABLE table_name COLUMNS col_1, col_2, ... , col_n syntax. The syntax allows collecting statistics only on a portion of the columns in wide tables, which improves the speed of statistics collection

Bug Fixes

• Fix an error that occurs during execution caused by the wrong execution plan. The wrong execution plan is caused by the shallow copy of schema columns when pushing down the aggregation operators on partitioned tables. #27797 #26554
• Fix the issue that plan-cache cannot detect changes of unsigned flags #28254
• Fix the wrong partition pruning when the partition function is out of range #28233
• Fix the issue that planner might cache invalid plans for join in some cases #28087
• Fix wrong index hash join when hash column type is enum #27893
• Fix a batch client bug that recycling idle connection might block sending requests in some rare cases #27688
• Fix the TiDB Lightning panic issue when it fails to perform checksum on a target cluster #27686
• Fix wrong results of the date_add and date_sub functions in some cases #27232
• Fix wrong results of the hour function in vectorized expression #28643
• Fix the authenticating issue when connecting to MySQL 5.1 or an older client version #27855
• Fix the issue that auto analyze might be triggered out of the specified time when a new index is added #28698
• Fix a bug that setting any session variable invalidates tidb_snapshot #28683
• Fix a bug that BR is not working for clusters with many missing-peer regions #27534
• Fix the unexpected error like tidb_cast to Int32 is not supported when the unsupported cast is pushed down to TiFlash #23907
• Fix the issue that DECIMAL overflow is missing in the %s value is out of range in '%s'error message #27964
• Fix a bug that the availability detection of MPP node does not work in some corner cases #3118
• Fix the DATA RACE issue when assigning MPP task ID #27952
• Fix the INDEX OUT OF RANGE error for a MPP query after deleting an empty dual table. #28250
• Fix the issue of false positive error log invalid cop task execution summaries length for MPP queries #1791
• Fix the issue of error log cannot found column in Schema column for MPP queries #28149
• Fix the issue that TiDB might panic when TiFlash is shuting down #28096
• Remove the support for insecure 3DES (Triple Data Encryption Algorithm) based TLS cipher suites #27859
• Fix the issue that Lightning connects to offline TiKV nodes during pre-check and causes import failures #27826
• Fix the issue that pre-check cost too much time when importing many files to tables #27605
• Fix the issue that rewriting expressions makes between infer wrong collation #27146
• Fix the issue that group_concat function did not consider the collation #27429
• Fix the result wrong that occurs when the argument of the extract function is a negative duration #27236
• Fix the issue that creating partition fails if NO_UNSIGNED_SUBTRACTION is set #26765
• Avoid expressions with side effects in column pruning and aggregation pushdown #27106
• Remove useless gRPC logs #24190
• Limit the valid decimal length to fix precision-related issues #3091
• Fix the issue of a wrong way to check for overflow in plus expression #26977
• Fix the issue of data too long error when dumping statistics from the table with new collation data #27024
• Fix the issue that the retried transactions' statements are not included in TIDB_TRX #28670
• Fix the wrong default value of the plugin_dir configuration 28084

tidb-server v5.2.3

There is no release note for this version.

tidb-server v5.2.2

Improvements

• Show the affected SQL statements in the debug log when the coprocessor encounters a lock, which is helpful in diagnosing problems #27718
• Support showing the size of the backup and restore data when backing up and restoring data in the SQL logical layer #27247

Bug Fixes

• Fix the issue that plan-cache cannot detect changes of unsigned flags #28254
• Fix the wrong partition pruning when the partition function is out of range #28233
• Fix the issue that planner may cache invalid plans for join in some cases #28087
• Fix wrong index hash join when hash column type is enum #27893
• Fix a batch client bug that recycling idle connection may block sending requests in some rare cases #27688
• Fixed the TiDB Lightning panic issue when it fails to perform checksum on a target cluster #27686
• Fix wrong results of the date_add and date_sub functions in some cases #27232
• Fix wrong results of the hour function in vectorized expression #28643
• Fix the authenticating issue when connecting to MySQL 5.1 or an older client version #27855
• Fix the issue that auto analyze might be triggered out of the specified time when a new index is added #28698
• Fix a bug that setting any session variable can make tidb_snapshot unwork #28683
• Fix a bug that BR is not working for clusters with many missing-peer regions #27534
• Fix the unexpected error like tidb_cast to Int32 is not supported when the unsupported cast is pushed down to TiFlash #23907
• Fix the issue that DECIMAL overflow is missing in the %s value is out of range in '%s'error message #27964
• Fix a bug that the availability detection of MPP node does not work in some corner cases #3118
• Fix theDATA RACE issue when assigningMPP task ID #27952
• Fix the INDEX OUT OF RANGE error for a MPP query after deleting an empty dual table. #28250
• Fix the issue of false positive error log invalid cop task execution summaries length for MPP queries #1791
• Fix the issue of error log can not found column in Schema column for MPP queries #28149
• Fix the issue that TiDB might crash when TiFlash shuts down #28096
• Remove the support for insecure 3DES (Triple Data Encryption Algorithm) based TLS ciphersuites #27859
• Fix the issue that Lightning connects to offline TiKV nodes during pre-check and causes import failures #27826
• Fix the issue that pre-check cost too much time when importing many files to tables #27605
• Fix the issue that rewriting expressions makes between infer wrong collation #27146
• Fix the issue that group_concat function did not consider the collation #27429
• Fix the issue that extract function gives wrong results when argument is a negative duration #27236
• Fix the issue that creating partition fails if NO_UNSIGNED_SUBTRACTION is set #26765
• Avoid expressions with side effects in column pruning and aggregation pushdown #27106
• Remove useless GRPC log in production #24190
• Limit the valid decimal length to fix precision-related issues #3091
• Fix the issue of a wrong way to check for overflow in plus expression #26977
• Fix the issue of data too long error when dumping statistics from the table with new collation data #27024
• Fix the issue that the retried transactions' statements are not included in TIDB_TRX #28670

tidb-server v5.1.3

There is no release note for this version.