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https://dev.mysql.com/doc/refman/8.4/en/innodb-persistent-stats.html
The persistent optimizer statistics feature improves plan stability by storing statistics to disk and making them persistent across server restarts so that the optimizer is more likely to make consistent choices each time for a given query. You ...
https://dev.mysql.com/doc/refman/8.4/en/optimizer-statistics.html
The column_statistics data dictionary table stores histogram statistics about column values, for use by the optimizer in constructing query execution plans. The column_statistics table has these characteristics: The table contains statistics for ...
https://dev.mysql.com/doc/refman/8.4/en/index-statistics.html
Storage engines collect statistics about tables for use by the optimizer. Table statistics are based on value groups, where a value group is a set of rows with the same key prefix value. For optimizer purposes, an important statistic is the average ...When a given index value yields a large number of rows, the index is less useful and MySQL is less likely to use ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-statistics-estimation.html
Optimizer statistics are not persisted to disk when innodb_stats_persistent=OFF or when individual tables are created or altered with STATS_PERSISTENT=0. Instead, statistics are stored in memory, and are lost when the server is shut down. Statistics ...Enabling innodb_stats_on_metadata may reduce access speed for schemas that have a large number of tables or indexes, and reduce stability of execution plans for queries that involve InnoDB ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-statistics-table.html
The information_schema_stats_expiry system variable defines the period of time before cached table statistics expire. If there are no cached statistics or statistics have expired, statistics are retrieved from storage engines when querying table ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-log-statistics.html
The NDB management client's CLUSTERLOG STATISTICS command can provide a number of useful statistics in its output. All operations within the same transaction use the same transaction coordinator, which reports the following statistics: Trans count.
https://dev.mysql.com/doc/refman/8.4/en/innodb-performance-optimizer-statistics.html
This section describes how to configure persistent and non-persistent optimizer statistics for InnoDB tables. Persistent optimizer statistics are persisted across server restarts, allowing for greater plan stability and more consistent query ...You ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndb-api-statistics.html
A number of types of statistical counters relating to actions performed by or affecting Ndb objects are available. Each NDB API statistics counter is listed in the following table with a description as well as the names of any MySQL server status ...Such actions include starting and closing (or aborting) transactions; primary key and unique key operations; table, range, and pruned scans; threads blocked while waiting for the completion of various operations; and data and events sent and received by ...
https://dev.mysql.com/doc/mysql-monitor/8.0/en/mem-reports-table-statistics.html
The Table Statistics report is based on the table statistics sys schema view, schema_table_statistics. Table View The table view lists the statistics in a standard table format. Figure 30.7 Table Statistics Report - Table View Treemap View The ...
https://dev.mysql.com/doc/mysql-monitor/8.0/en/mem-reports-user-statistics.html
The User Statistics report is based on the user summary sys schema views. Table View The table view lists the statistics in a standard table format. Figure 30.9 User Statistics Report - Table View Existing users who have never logged on to the ...