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https://dev.mysql.com/doc/refman/8.4/en/explain-extended.html
The Message value in SHOW WARNINGS output displays how the optimizer qualifies table and column names in the SELECT statement, what the SELECT looks like after the application of rewriting and optimization rules, and possibly other notes about the ... The EXPLAIN statement produces extra (“extended”) information that is not part of EXPLAIN output but can be viewed by issuing a SHOW WARNINGS statement following ...
https://dev.mysql.com/doc/refman/8.4/en/join.html
Index hints can be specified to affect how the MySQL optimizer makes use of indexes. Optimizer hints and the optimizer_switch system variable are other ways to influence optimizer use of indexes. This includes a join handled by merging derived ...
https://dev.mysql.com/doc/refman/8.4/en/system-schema.html
Data Dictionary Tables Grant System Tables Object Information System Tables Log System Tables Server-Side Help System Tables Time Zone System Tables Replication System Tables Optimizer System Tables Miscellaneous System Tables The remainder of this ...It contains tables that store information required by the MySQL server as it ...
https://dev.mysql.com/doc/refman/8.4/en/descending-indexes.html
Descending indexes also make it possible for the optimizer to use multiple-column indexes when the most efficient scan order mixes ascending order for some columns and descending order for others. Indexes that have descending key parts are not used ... MySQL supports descending indexes: DESC in an index definition is no longer ignored but causes storage of key values in descending ...
https://dev.mysql.com/doc/refman/8.4/en/index-statistics.html
Storage engines collect statistics about tables for use by the optimizer. For optimizer purposes, an important statistic is the average value group size. For optimization purposes, the relevant value is the average size of the non-NULL value groups. This makes index appear to the optimizer to be less useful than it really is for joins that look for non-NULL ...
https://dev.mysql.com/doc/refman/8.4/en/json.html
The MySQL optimizer also looks for compatible indexes on virtual columns that match JSON expressions. Partial Updates of JSON Values In MySQL 8.4, the optimizer can perform a partial, in-place update of a JSON column instead of removing the old ...
https://dev.mysql.com/doc/refman/8.4/en/select.html
tbl_name [[AS] alias] [index_hint] The use of index hints provides the optimizer with information about how to choose indexes during query processing. (If no GROUP BY is present, all rows implicitly form a single aggregate group.) The HAVING clause ... SELECT [ALL | DISTINCT | DISTINCTROW ] [HIGH_PRIORITY] [STRAIGHT_JOIN] [SQL_SMALL_RESULT] [SQL_BIG_RESULT] [SQL_BUFFER_RESULT] [SQL_NO_CACHE] [SQL_CALC_FOUND_ROWS] select_expr [, select_expr] ...
https://dev.mysql.com/doc/mysql-enterprise-backup/8.4/en/backup-capacity-options.html
See Section 13.1, “Optimizing Backup Performance” and Section 13.2, “Optimizing Restore Performance” for additional advice about recommended combinations of values for this and other performance-related options for various hardware ... These ...
https://dev.mysql.com/doc/mysql-monitor/8.0/en/performance-advisors-ref.html
For optimal performance, transactions that move through the binary log should be contained within the binary log cache. Default frequency 00:05:00 Default auto-close enabled no InnoDB Buffer Pool Writes May Be Performance Bottleneck For optimal ...
https://dev.mysql.com/doc/heatwave/en/mys-hwaml-ml-train.html
optimization_metric: The scoring metric to optimize for when training a machine learning model. It identifies the optimal weight between the two components based on the metric. Anomaly detection models don't support the following options during ...