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https://dev.mysql.com/doc/refman/8.4/en/keywords.html
Certain keywords, such as SELECT, DELETE, or BIGINT, are reserved and require special treatment for use as identifiers such as table and column names. This may also be true for the names of built-in functions. Some keywords which are otherwise ...
https://dev.mysql.com/doc/refman/8.4/en/limit-optimization.html
If you need only a specified number of rows from a result set, use a LIMIT clause in the query, rather than fetching the whole result set and throwing away the extra data. MySQL sometimes optimizes a query that has a LIMIT row_count clause and no ...
https://dev.mysql.com/doc/refman/8.4/en/optimizing-innodb-bulk-data-loading.html
These performance tips supplement the general guidelines for fast inserts in Section 10.2.5.1, “Optimizing INSERT Statements”. When importing data into InnoDB, turn off autocommit mode, because it performs a log flush to disk for every insert.
https://dev.mysql.com/doc/refman/8.4/en/partitioning-limitations.html
This section discusses current restrictions and limitations on MySQL partitioning support. The following constructs are not permitted in partitioning expressions: Stored procedures, stored functions, loadable functions, or plugins. For a list of ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-functions.html
MySQL includes built-in SQL functions that format or retrieve Performance Schema data, and that may be used as equivalents for the corresponding sys schema stored functions. The built-in functions can be invoked in any schema and require no ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-optimization.html
Applications that monitor databases may make frequent use of Performance Schema tables. To write queries for these tables most efficiently, take advantage of their indexes. For example, include a WHERE clause that restricts retrieved rows based on ...
https://dev.mysql.com/doc/refman/8.4/en/replication-gtids-concepts.html
A global transaction identifier (GTID) is a unique identifier created and associated with each transaction committed on the server of origin (the source). This identifier is unique not only to the server on which it originated, but is unique across ...
https://dev.mysql.com/doc/refman/8.4/en/sys-ps-thread-id.html
Note ps_thread_id() is deprecated, and subject to removal in a future MySQL version. Applications that use it should be migrated to use the built-in PS_THREAD_ID() and PS_CURRENT_THREAD_ID() functions instead. See Section 14.21, “Performance ...
https://dev.mysql.com/doc/refman/8.4/en/sys-schema-auto-increment-columns.html
This view indicates which tables have AUTO_INCREMENT columns and provides information about those columns, such as the current and maximum column values and the usage ratio (ratio of used to possible values). By default, rows are sorted by ...
https://dev.mysql.com/doc/refman/8.4/en/update.html
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 accessible within the UPDATE. Single-table syntax: UPDATE [LOW_PRIORITY] [IGNORE] table_reference SET ...