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https://dev.mysql.com/doc/refman/8.4/en/implicit-commit.html
Transaction-control and locking statements are exceptions: If an implicit commit occurs before execution, another does not occur after. BEGIN, LOCK TABLES, SET autocommit = 1 (if the value is not already 1), START TRANSACTION, UNLOCK TABLES. UNLOCK ... The statements listed in this section (and any synonyms for them) implicitly end any transaction active in the current session, as if you had done a COMMIT before executing the ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-online-ddl.html
For in-place operations, the ability to adjust the balance between performance and concurrency during DDL operations using the LOCK clause. By default, MySQL performs the operation instantly or in place, as permitted, with as little locking as ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-performance-ro-txn.html
A transaction ID is only needed for a transaction that might perform write operations or locking reads such as SELECT ... You can still make changes to session-specific temporary tables in a read-only transaction, or issue locking queries for them, ... InnoDB can avoid the overhead associated with setting up the transaction ID (TRX_ID field) for transactions that are known to be ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-table-reference.html
The following table summarizes all available Performance Schema tables. For greater detail, see the individual table descriptions. Table 29.1 Performance Schema Tables Table Name Description accounts Connection statistics per client account ...
https://dev.mysql.com/doc/mysql-enterprise-backup/8.4/en/mysqlbackup.backup.html
240426 13:01:24 RDR1 INFO: The server instance is locked for backup. 240426 13:01:24 RDR1 INFO: The server instance is unlocked after 0.003 seconds. 240426 13:01:24 RDR1 INFO: The server instance is locked for backup. 240426 13:01:24 RDR1 INFO: ...
https://dev.mysql.com/doc/internals/en/flush-tables.html
The current refresh_version is also compared to the open refresh_version after a thread gets a lock on a table. If the refresh version is different, the thread will free all locks, reopen the table and try to get the locks again. If the thread that ...The idea of FLUSH TABLES is to force all tables to be ...
https://dev.mysql.com/doc/refman/8.4/en/mysqldumpslow.html
The MySQL slow query log contains information about queries that take a long time to execute (see Section 7.4.5, “The Slow Query Log”). mysqldumpslow parses MySQL slow query log files and summarizes their contents. Normally, mysqldumpslow ...
https://dev.mysql.com/doc/refman/8.4/en/privileges-provided.html
LOCK TABLES Enables use of explicit LOCK TABLES statements to lock tables for which you have the SELECT privilege. This includes use of write locks, which prevents other sessions from reading the locked table. AUDIT_ABORT_EXEMPT Allows queries ...
https://dev.mysql.com/doc/refman/8.4/en/replication-howto-masterstatus.html
Warning This procedure uses FLUSH TABLES WITH READ LOCK, which blocks COMMIT operations for InnoDB tables. Choose one of the following options: If you have existing data that needs be to synchronized with the replica before you start replication, ...
https://dev.mysql.com/doc/internals/en/myisam-concurrent-insert.html
The copy back is done in mi_update_status(), which is called from mi_lock_database() when unlocking from a write lock. This, in turn, is called from ha_myisam::external_lock() from unlock_external() from mysql_unlock_tables(). So it was possible ...