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https://dev.mysql.com/doc/connector-j/en/connector-j-usagenotes-j2ee-concepts-connection-pooling.html
Connection pooling is a technique of creating and managing a pool of connections that are ready for use by any thread that needs them. Connection pooling can greatly increase the performance of your Java application, while reducing overall resource ...
https://dev.mysql.com/doc/refman/8.4/en/analyze-table.html
In the few cases that ANALYZE TABLE does not produce values good enough for your particular tables, you can use FORCE INDEX with your queries to force the use of a particular index, or set the max_seeks_for_key system variable to ensure that MySQL ...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/ansi-diff-foreign-keys.html
For example, if you define a RESTRICT type constraint, and there is a child row with several parent rows, InnoDB does not permit the deletion of any of the parent rows. This means that you cannot use self-referential ON UPDATE CASCADE or ON UPDATE ...
https://dev.mysql.com/doc/refman/8.4/en/audit-log-reference.html
audit_log_policy Command-Line Format --audit-log-policy=value Deprecated Yes System Variable audit_log_policy Scope Global Dynamic No SET_VAR Hint Applies No Type Enumeration Default Value ALL Valid Values ALLLOGINSQUERIESNONE Note This deprecated ...Unless those objects are installed, the audit_log plugin operates in (deprecated) legacy ...
https://dev.mysql.com/doc/refman/8.4/en/column-count-limit.html
This section describes limits on the number of columns in tables and the size of individual rows. Column Count Limits Row Size Limits Column Count Limits MySQL has hard limit of 4096 columns per table, but the effective maximum may be less for a ...
https://dev.mysql.com/doc/refman/8.4/en/communication-errors.html
Other reasons for problems with aborted connections or aborted clients: The max_allowed_packet variable value is too small or queries require more memory than you have allocated for mysqld. If connection problems occur such as communication errors ...
https://dev.mysql.com/doc/refman/8.4/en/constant-folding-optimization.html
Comparisons between constants and column values in which the constant value is out of range or of the wrong type with respect to the column type are now handled once during query optimization rather row-by-row than during execution. The comparisons ...
https://dev.mysql.com/doc/refman/8.4/en/create-procedure.html
By default, a stored routine is associated with the default database. To associate the routine explicitly with a given database, specify the name as db_name.sp_name when you create it. The CREATE FUNCTION statement is also used in MySQL to support ...
https://dev.mysql.com/doc/refman/8.4/en/create-table-secondary-indexes.html
It is also possible to create an index on a JSON column using the JSON_VALUE() function with an expression that can be used to optimize queries employing the expression. A secondary index defined on a virtual column is sometimes referred to as a ...
https://dev.mysql.com/doc/refman/8.4/en/create-table.html
RANGE COLUMNS(column_list) This variant on RANGE facilitates partition pruning for queries using range conditions on multiple columns (that is, having conditions such as WHERE a = 1 AND b < 10 or WHERE a = 1 AND b = 10 AND c < 10). LIST ...| ...