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https://dev.mysql.com/doc/refman/8.4/en/performance-schema-persisted-variables-table.html
The persisted_variables table provides an SQL interface to the mysqld-auto.cnf file that stores persisted global system variable settings, enabling the file contents to be inspected at runtime using SELECT statements. The table contains a row for ...Variables are persisted using SET PERSIST or PERSIST_ONLY statements; see Section 15.7.6.1, “SET Syntax for Variable ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-replication-applier-configuration-table.html
This table shows the configuration parameters that affect transactions applied by the replica. Parameters stored in the table can be changed at runtime with the CHANGE REPLICATION SOURCE TO statement. The replication_applier_configuration table has ...There is always a default replication channel, and more replication channels can be ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-replication-applier-status-by-coordinator-table.html
For a multithreaded replica, the replica uses multiple worker threads and a coordinator thread to manage them, and this table shows the status of the coordinator thread. For a multithreaded replica, the replication_applier_status_by_worker table ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-replication-applier-status-by-worker-table.html
This table provides details of the transactions handled by applier threads on a replica or Group Replication group member. A multithreaded replica also has a coordinator thread to manage the applier threads, and the status of this thread is shown ...For a single-threaded replica, data is shown for the replica's single applier ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-session-account-connect-attrs-table.html
For descriptions of common attributes, see Section 29.12.9, “Performance Schema Connection Attribute Tables”. The session_account_connect_attrs table contains connection attributes only for the current session, and other sessions associated with ... Application programs can provide key-value connection attributes to be passed to the server at connect ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-session-connect-attrs-table.html
For descriptions of common attributes, see Section 29.12.9, “Performance Schema Connection Attribute Tables”. To see connection attributes only for the current session, and other sessions associated with the session account, use the ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-setup-consumers-table.html
The setup_consumers table has these indexes: Primary key on (NAME) TRUNCATE TABLE is not permitted for the setup_consumers table. For detailed information about the effect of enabling different consumers, see Section 29.4.7, “Pre-Filtering by ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-variables-info-table.html
The variables_info table shows, for each system variable, the source from which it was most recently set, and its range of values. VARIABLE_SOURCE The source from which the variable was most recently set: COMMAND_LINE The variable was set on the ...
https://dev.mysql.com/doc/refman/8.4/en/replication-features-repair-table.html
When used on a corrupted or otherwise damaged table, it is possible for the REPAIR TABLE statement to delete rows that cannot be recovered. However, any such modifications of table data performed by this statement are not replicated, which can ...
https://dev.mysql.com/doc/refman/8.4/en/subquery-optimization.html
Note A limitation on UPDATE and DELETE statements that use a subquery to modify a single table is that the optimizer does not use semijoin or materialization subquery optimizations. As a workaround, try rewriting them as multiple-table UPDATE and ...