Kernel Version Release History

Date

Description

2023-11-24

• New features and optimized features:
  • Added forward compatibility of datatime, timestamp, and time field behaviors.
  • Added HASH JOIN on disks in PQ.
  • Added INSERT and REPLACE SELECT functions in PQ.
  • Added log printing mechanism for connection and disconnection, which helps you locate connection-related issues quickly.
  • Added some useful information in slow query logs, which helps you locate slow SQL statements.
  • Allowed you to dynamically enable binlog.
  • Optimized the NDP bloom filter.
  • Allowed you to use CAST (...) AS INT) syntax.
  • Optimized the Nested Loop Join + Distinct performance.
  • Identified slice ID corresponding to the slow I/O quickly.
  • Added the sal_init log, which helps you to locate storage timeout issues.
• Resolved issue description:
  • There are trx_id and cpu_time fields in full SQL statements.
  • Character strings can be converted into INT in WHERE conditions of PREPARE statements.
  • No crash issue occurs when DDL operations and queries are concurrently accessed.
  • The binlogs that are sharply generated in a short period of time can be cleared in a timely manner.
  • Execution results are correct after PQ is enabled for multi-table JOIN SQL statements.
  • Backward Index Scan is compatible with ICP.
  • weight_string functions support LEVEL clauses.
  • The results of the same SQL statement using different indexes are consistent.
  • When NDP and PQ are enabled at the same time, recycle LSN is correct.

Date

Description

2023-08-31

• New features and optimized features:
  • Supported for storing full and incremental backups on read replicas, which reduce the memory and CPU usage.
  • Optimized UNDO damage location: When the undo damage occurs during startup, the undo damage log and the corresponding table name are printed.
  • Improved the query performance of read replicas.
  • Added the conversion of IN predicates to subqueries.
  • Large-scale commercial use of the NDP feature.
  • Optimized execution planes using statement outline.
  • Added support for round functions in PQ.
• Resolved issue description:
  • The ORDER BY LIMIT and ORDER LIMIT result sets do not overlap when fast sorting and priority queue sorting algorithms are used.
  • Returned results are correct for PQ statements.
  • No errors are reported when PREPARE statements are executed.
  • No PQ assertion errors are reported on UNION queries.
  • When a large amount of data is inserted into the primary node, a read replica is promoted to the primary. After the promotion is successful, the results of full-text index queries are correct.
  • When read replicas use the general_log and slow_log tables, warning logs will not be displayed.
  • After the value of the parameter innodb_lock_wait_timeout is changed, the actual timeout wait time is correct.
  • When a read replica is promoted to primary, there is no the error "Failed to find page in slice manager"
  • The percentage for the PWAL scanning progress in the SALSQL log cannot exceed 100%.
  • When the sqlsmith tool is executed, there is no the error "mysqld coredump" in the EXPLAIN phase of query statements.
  • In SELECT DISTINCT CAST functions, datetime can be converted float type.

2023-05-11

• New features and optimized features:
  • Supported small-scale instances.
  • Optimized the solution when DDL statements on standby nodes fail.
  • Optimized the capacity calculation of salsql.
  • Supported the restriction on resources of a single SQL statement.
  • Supported the use of per thread for admin port and local socket.
  • Optimized the memory of pwalScanner.
  • Supported the modification of default_collation_for_utf8mb4 parameter.
  • Supported diagnosis on large transactions.
  • Supported the killing of idle transactions.
  • Accelerated incremental restoration.
  • Added database and account descriptions.
  • Supported the acceleration of buffer pool resize.
• Resolved issue description:
  • Ptrc does not lead to inconsistent execution results of Nestedloop join.
  • No crash issue occurs when subqueries are sorted using Windows functions.
  • When using rewrites view, tables are not evaluated to turn left joins into inner joins.
  • Execution results are returned from decimal data that meets specified filter criteria.
  • Memory is aligned.
  • Scan_row is correctly recorded in full logs.

2023-05-17

Errors of exceeded sorting memory are not reported for columns containing large JSON data.

2023-04-02

Character sets are not used in combination in prepare statements.

2023-03-14

• New features:

  Reduced primary/standby latency.

• Resolved issues:
  • No error occurs when JSON-related functions are used in prepare statements.
  • Query results are returned when filter criteria are specified.
  • No null pointer error is reported after Windows functions generate a temporary disk table.
  • The crash issue caused by the use of null pointers in Windows functions is resolved.
  • Prepare statements are executed successfully.

2023-01-11

• New features
  • Supported SQL statement concurrency control.
  • Optimized read flow control.
  • Optimized the consistency of primary/standby execution plan.
  • Pre-created slices asynchronously.
• Resolved issues
  • No crash issue occurs when the system variable INNODB_VALIDATE_TABLESPACE_PATHS is disabled and the undo space truncate command is executed.
  • The query of information_schema.innodb_trx is fast.
  • The issue of inconsistent results is resolved: left joins now are turned into inner joins.
  • The crash issue caused by subquery optimization is resolved.
  • Values of the Instant field are correctly obtained under concurrent instantDDL and DML operations.
  • No OOM issue occurs when two InnoDB tables with FTS indexes are loaded.
  • No OOM issue occurs when the data dictionary of millions of tables is being updated.

2022-12-07

Scan errors triggered by Skip Scans are not displayed when a table with virtual columns is updated.

2022-11-16

During a primary/standby switchover, databases will not break down when connecting to the standby instance times out.

2022-09-23

• The If(...) statement in Condition_pushdown::replace_columns_in_cond is modified.
• The database does not break down when:
  • Storage functions are invoked recursively.
  • Multiple tables are deleted or full-text search is performed.
  • SQL query statements of multiple window functions are executed.
• Users with global permission can successfully run SHOW CREATE DATABASE.

2022-08-25

The ptrc crash problem in stored procedure is resolved.

2022-07-22

• Databases will not break down due to empty accounts.
• When a temporary table used for aggregation is updated, BLOB points to the latest data.

2022-05-16

• New features
  • You can enable or disable orphaned definer check control.
  • GaussDB(for MySQL) supports transparent transmission of proxy IP addresses.
  • You can set the consistency level of your proxy instances to session consistency.
• Resolved issues
  • The data dictionary on standby nodes is updated if DDL statements on the primary node are not submitted.
  • During a failover, the auto increment of the primary node is not rolled back.
  • The performance issue of standby nodes is resolved.

2022-08-12

• New features and performance optimized
  • Supported SQL statement concurrency control.
  • Added a limit to concurrent numbers of Faster DDL.
  • Supported all Faster DDL operations in row format.
  • Extended full SQL fields.
  • Optimized flow control.
  • Supported the quick timeout of ALTER TABLE.
  • Supported the query of plan cache.
  • Optimized statistics on standby nodes.
• Resolved issues
  • Standby nodes do not break down after partition-table on the primary node is renamed.
  • The default buffer size of SQL tracer is modified.
  • When the truncate lsn of standby nodes lags behind, the standby nodes can start successfully.
  • The execution plan error is not displayed when SQL queries with the same range are executed.
  • The crash issue caused by empty accounts is resolved.
  • The crash issue caused by database dropping is resolved.