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https://dev.mysql.com/doc/refman/8.4/en/checksum-table.html
For example, the storage format for temporal types such as TIME, DATETIME, and TIMESTAMP changed in MySQL 5.6 prior to MySQL 5.6.5, so if a 5.5 table is upgraded to MySQL 5.6, the checksum value may change. For large tables, this could take a long ...[QUICK | EXTENDED] CHECKSUM TABLE reports a checksum for the contents of a ...
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. To update cached values at any time for a given table, use ANALYZE TABLE. The higher the cardinality, the greater the chance that ...If there are no cached statistics or statistics have expired, statistics are retrieved from storage engines when querying table statistics ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-benefits.html
InnoDB tables have the following benefits: If the server unexpectedly exits because of a hardware or software issue, regardless of what was happening in the database at the time, you don't need to do anything special after restarting the database.
https://dev.mysql.com/doc/refman/8.4/en/myisamchk-general-options.html
This option is available only if MySQL was built using WITH_DEBUG. MySQL release binaries provided by Oracle are not built using this option. If you are running mysqld with external locking disabled, the table can be locked only by another myisamchk ... The options described in this section can be used for any type of table maintenance operation performed by ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-variables-info-table.html
PERSISTED The variable was set from a server-specific mysqld-auto.cnf option file. SERVER The variable was set from a server-specific $MYSQL_HOME/my.cnf option file. For details about how MYSQL_HOME is set, see Section 6.2.2.2, “Using Option ...
https://dev.mysql.com/doc/refman/8.4/en/stored-routines-syntax.html
MySQL supports a very useful extension that enables the use of regular SELECT statements (that is, without using cursors or local variables) inside a stored procedure. Multiple SELECT statements generate multiple result sets, so the client must use ... A stored routine is either a procedure or a ...
https://dev.mysql.com/doc/refman/8.4/en/update.html
Each matching row is updated once, even if it matches the conditions multiple times. If you set a column to the value it currently has, MySQL notices this and does not update it. The implicit default value is 0 for numeric types, the empty string ...
https://dev.mysql.com/doc/mysql-ai/9.5/en/mys-ai-aml-prepare-data-split.html
The following data types for this column are supported: DATETIME TIMESTAMP DATE TIME YEAR semisupervised: If running an anomaly detection task, set this to true for semi-supervised learning, or false for unsupervised learning. mysql> CALL ... You ...
https://dev.mysql.com/doc/mysql-ai/9.5/en/mys-mysqlai-ml-generate.html
It is suggested that: To generate the same output for a particular prompt every time you run it, set the temperature to 0. To generate a random new statement for a particular prompt every time you run it, increase the temperature. The ML_GENERATE ...
https://dev.mysql.com/doc/mysql-em-plugin/en/myoem-metric-sysschema-statementanalysis-total-executions-category.html
Table 6.39 Sys Schema Statement Analysis by Total Executions Metrics NameDescriptionAvg Latency The average wait time per timed occurrence of the statement. Avg Time of Execution The average time the statement takes to execute. Exec Count The total ... Lists the Sys Schema Statement Analysis by Total Executions metrics and provides a brief description of ...