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https://dev.mysql.com/doc/refman/8.4/en/order-by-optimization.html
In MySQL 8.4, that no longer occurs, so specifying ORDER BY NULL at the end to suppress implicit sorting (as was done previously) is no longer necessary. This section describes when MySQL can use an index to satisfy an ORDER BY clause, the filesort ...
https://dev.mysql.com/doc/refman/8.4/en/pam-pluggable-authentication.html
Note PAM pluggable authentication is an extension included in MySQL Enterprise Edition, a commercial product. MySQL Enterprise Edition supports an authentication method that enables MySQL Server to use PAM (Pluggable Authentication Modules) to ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning.html
See Section 28.3.21, “The INFORMATION_SCHEMA PARTITIONS Table”, for more information; for some examples of queries against this table, see Section 26.2.7, “How MySQL Partitioning Handles NULL”. Note Table partitioning differs from ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-clone-status-table.html
The clone_status table shows the status of the current or last executed cloning operation only. The table only ever contains one row of data, or is empty. The clone_status table has these columns: ID A unique cloning operation identifier in the ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-connection-tables.html
The Performance Schema also counts internal threads and threads for user sessions that failed to authenticate, using rows with USER and HOST column values of NULL. When a client connects to the MySQL server, it does so under a particular user name ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-consumer-filtering.html
Conversely, you can get detailed statements in events_statements_current without digests (the DIGEST and DIGEST_TEXT columns are NULL in this case). To enable or disable a consumer, set its ENABLED value to YES or NO. If you disable a consumer, the ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-error-log-table.html
Of the logs the MySQL server maintains, one is the error log to which it writes diagnostic messages (see Section 7.4.2, “The Error Log”). Typically, the server writes diagnostics to a file on the server host or to a system log service.
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-host-cache-table.html
HOST The resolved DNS host name for that client IP, or NULL if the name is unknown. The MySQL server maintains an in-memory host cache that contains client host name and IP address information and is used to avoid Domain Name System (DNS) lookups.
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-hosts-table.html
This is NULL for an internal thread, or for a user session that failed to authenticate. The hosts table contains a row for each host from which clients have connected to the MySQL server. For each host name, the table counts the current and total ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-performance-timers-table.html
For an explanation of how event timing occurs, see Section 29.4.1, “Performance Schema Event Timing”. For a cycle timer, the frequency is generally related to the CPU speed. For example, on a system with a 2.4GHz processor, the CYCLE may be ...