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https://dev.mysql.com/doc/refman/8.4/en/mysqldumpslow.html
MySQL release binaries provided by Oracle are not built using this option. 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 ...
https://dev.mysql.com/doc/refman/8.4/en/operator-precedence.html
Operator precedences are shown in the following list, from highest precedence to the lowest. Operators that are shown together on a line have the same precedence. When used as a comparison operator, it has the same precedence as <=>, >=, >, <=, <, ...
https://dev.mysql.com/doc/refman/8.4/en/optimize-blob.html
When storing a large blob containing textual data, consider compressing it first. Do not use this technique when the entire table is compressed by InnoDB or MyISAM. For a table with several columns, to reduce memory requirements for queries that do ...
https://dev.mysql.com/doc/refman/8.4/en/optimize-table.html
OPTIMIZE TABLE reorganizes the physical storage of table data and associated index data, to reduce storage space and improve I/O efficiency when accessing the table. The exact changes made to each table depend on the storage engine used by that ...
https://dev.mysql.com/doc/refman/8.4/en/optimizer-statistics.html
The column_statistics data dictionary table stores histogram statistics about column values, for use by the optimizer in constructing query execution plans. The column_statistics table has these characteristics: The table contains statistics for ...
https://dev.mysql.com/doc/refman/8.4/en/packet-too-large.html
A communication packet is a single SQL statement sent to the MySQL server, a single row that is sent to the client, or a binary log event sent from a replication source server to a replica. The largest possible packet that can be transmitted to or ...
https://dev.mysql.com/doc/refman/8.4/en/partial-revokes.html
It is possible to grant privileges that apply globally if the partial_revokes system variable is enabled. Specifically, for users who have privileges at the global level, partial_revokes enables privileges for specific schemas to be revoked while ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-columns.html
The next two sections discuss COLUMNS partitioning, which are variants on RANGE and LIST partitioning. COLUMNS partitioning enables the use of multiple columns in partitioning keys. All of these columns are taken into account both for the purpose ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-key.html
Partitioning by key is similar to partitioning by hash, except that where hash partitioning employs a user-defined expression, the hashing function for key partitioning is supplied by the MySQL server. NDB Cluster uses MD5() for this purpose; for ...
https://dev.mysql.com/doc/refman/8.4/en/password-logging.html
Passwords can be written as plain text in SQL statements such as CREATE USER, GRANT and SET PASSWORD. If such statements are logged by the MySQL server as written, passwords in them become visible to anyone with access to the logs. Statement ...