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30.4.3.35 The statement_analysis and x$statement_analysis Views

https://dev.mysql.com/doc/refman/8.0/en/sys-statement-analysis.html

lock_latency The total time waiting for locks by timed occurrences of the statement. The statement_analysis and x$statement_analysis views have these columns: query The normalized statement string. db The default database for the statement, or NULL ...

30.4.3.45 The user_summary_by_statement_latency and x$user_summary_by_statement_latency Views

https://dev.mysql.com/doc/refman/8.0/en/sys-user-summary-by-statement-latency.html

lock_latency The total time waiting for locks by timed statements for the user. The user_summary_by_statement_latency and x$user_summary_by_statement_latency views have these columns: user The client user name. Rows for which the USER column in the ...

30.4.3.46 The user_summary_by_statement_type and x$user_summary_by_statement_type Views

https://dev.mysql.com/doc/refman/8.0/en/sys-user-summary-by-statement-type.html

lock_latency The total time waiting for locks by timed occurrences of the statement event for the user. These views summarize information about statements executed, grouped by user and statement type. By default, rows are sorted by user and ...

15.1.37 TRUNCATE TABLE Statement

https://dev.mysql.com/doc/refman/8.0/en/truncate-table.html

Truncation operations cannot be performed if the session holds an active table lock. Logically, TRUNCATE TABLE is similar to a DELETE statement that deletes all rows, or a sequence of DROP TABLE and CREATE TABLE statements. To achieve high ...

10.2.5.2 Optimizing UPDATE Statements

https://dev.mysql.com/doc/refman/8.0/en/update-optimization.html

Performing multiple updates together is much quicker than doing one at a time if you lock the table. An update statement is optimized like a SELECT query with the additional overhead of a write. The speed of the write depends on the amount of data ...

15.2.17 UPDATE Statement

https://dev.mysql.com/doc/refman/8.0/en/update.html

This affects only storage engines that use only table-level locking (such as MyISAM, MEMORY, and MERGE). UPDATE is a DML statement that modifies rows in a table. An UPDATE statement can start with a WITH clause to define common table expressions ...

3.4 What the MySQL Upgrade Process Upgrades

https://dev.mysql.com/doc/refman/8.0/en/upgrading-what-is-upgraded.html

Each table is locked and therefore unavailable to other sessions while it is being processed. Installing a new version of MySQL may require upgrading these parts of the existing installation: The mysql system schema, which contains tables that ...

2.3.5 Troubleshooting a Microsoft Windows MySQL Server Installation

https://dev.mysql.com/doc/refman/8.0/en/windows-troubleshooting.html

Fatal error: Can't open and lock privilege tables: Table 'mysql.user' doesn't exist These messages often occur when the MySQL base or data directories are installed in different locations than the default locations (C:\Program Files\MySQL\MySQL ...

15.3.8.3 Restrictions on XA Transactions

https://dev.mysql.com/doc/refman/8.0/en/xa-restrictions.html

If two XA transactions committed in parallel on the source are being prepared on the replica in the inverse order, locking dependencies can occur that cannot be safely resolved, and it is possible for replication to fail with deadlock on the replica. XA transaction support is limited to the InnoDB storage ...