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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/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 ...
https://dev.mysql.com/doc/relnotes/heatwave/en/news-8-0-30.html
Advisor MySQL HeatWave AutoML Functionality Added or Changed Advisor MySQL HeatWave Advisor Auto Encoding, which recommends string column encodings, now provides encoding recommendations that optimize query performance. Previously, string column ...
https://dev.mysql.com/doc/refman/8.4/en/analyze-table.html
You can make the statistics collected by ANALYZE TABLE more precise and more stable by enabling innodb_stats_persistent, as explained in Section 17.8.10.1, “Configuring Persistent Optimizer Statistics Parameters”. For more information about key ...ANALYZE [NO_WRITE_TO_BINLOG | LOCAL] TABLE tbl_name UPDATE HISTOGRAM ON col_name [, col_name] ...
https://dev.mysql.com/doc/refman/8.4/en/column-indexes.html
Optimizations are applied to certain kinds of FULLTEXT queries against single InnoDB tables. For this optimization to apply, there must be no WHERE clauses and only a single ORDER BY clause in descending order. For queries that contain full-text ...
https://dev.mysql.com/doc/refman/8.4/en/delete.html
The speed of delete operations may also be affected by factors discussed in Section 10.2.5.3, “Optimizing DELETE Statements”. To reclaim unused space and reduce file sizes, use the OPTIMIZE TABLE statement or the myisamchk utility to reorganize ... DELETE is a DML statement that removes rows from a ...