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https://dev.mysql.com/doc/refman/8.4/en/optimize-multi-tables.html
Some techniques for keeping individual queries fast involve splitting data across many tables. When the number of tables runs into the thousands or even millions, the overhead of dealing with all these tables becomes a new performance consideration.
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-instance-tables.html
They provide event names and explanatory notes or status information: cond_instances: Condition synchronization object instances file_instances: File instances mutex_instances: Mutex synchronization object instances rwlock_instances: Lock ...There ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-lock-tables.html
The Performance Schema exposes lock information through these tables: data_locks: Data locks held and requested data_lock_waits: Relationships between data lock owners and data lock requestors blocked by those owners metadata_locks: Metadata locks ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-tp-connections-table.html
The tp_connections table contains one row per connection managed by the Thread Pool plugin. The tp_connections table contains the following rows: CONNECTION_ID The connection ID as reported by SELECT CONNECTION_ID(). This column and ...Each row ...
https://dev.mysql.com/doc/refman/8.4/en/sys-table-exists.html
Tests whether a given table exists as a regular table, a TEMPORARY table, or a view. If both a temporary and a permanent table exist with the given name, TEMPORARY is returned. Parameters in_db VARCHAR(64): The name of the database in which to ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-auto-increment-handling.html
To make this clear, consider an example that uses this table: CREATE TABLE t1 ( c1 INT(11) NOT NULL AUTO_INCREMENT, c2 VARCHAR(10) DEFAULT NULL, PRIMARY KEY (c1) ) ENGINE=InnoDB; Suppose that there are two transactions running, each inserting rows ... InnoDB provides a configurable locking mechanism that can significantly improve scalability and performance of SQL statements that add rows to tables with AUTO_INCREMENT ...
https://dev.mysql.com/doc/refman/8.4/en/internal-locking.html
This section discusses internal locking; that is, locking performed within the MySQL server itself to manage contention for table contents by multiple sessions. Row-Level Locking Table-Level Locking Choosing the Type of Locking Row-Level Locking ...
https://dev.mysql.com/doc/refman/8.4/en/ansi-diff-select-into-table.html
For example: INSERT INTO tbl_temp2 (fld_id) SELECT tbl_temp1.fld_order_id FROM tbl_temp1 WHERE tbl_temp1.fld_order_id > 100; Alternatively, you can use SELECT ... The same syntax can also be used inside stored routines using cursors and local ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-connection-attribute-tables.html
These Performance Schema tables expose attribute information: session_account_connect_attrs: Connection attributes for the current session, and other sessions associated with the session account session_connect_attrs: Connection attributes for all ... Connection attributes are key-value pairs that application programs can pass to the server at connect ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-miscellaneous-tables.html
The following sections describe tables that do not fall into the table categories discussed in the preceding sections: component_scheduler_tasks: The current status of each scheduled task. user_defined_functions: Loadable functions registered by a ...