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https://dev.mysql.com/doc/refman/8.4/en/delete.html
DELETE is a DML statement that removes rows from a table. A DELETE statement can start with a WITH clause to define common table expressions accessible within the DELETE. Single-Table Syntax DELETE [LOW_PRIORITY] [QUICK] [IGNORE] FROM tbl_name ...
https://dev.mysql.com/doc/refman/8.4/en/extensions-to-ansi.html
MySQL Server supports some extensions that you are not likely to find in other SQL DBMSs. Be warned that if you use them, your code is most likely not portable to other SQL servers. For example, MySQL Server recognizes the STRAIGHT_JOIN keyword in ...
https://dev.mysql.com/doc/refman/8.4/en/function-optimization.html
A function is nondeterministic if, given fixed values for its arguments, it can return different results for different invocations. If a function is tagged nondeterministic, a reference to it in a WHERE clause is evaluated for every row (when ...
https://dev.mysql.com/doc/refman/8.4/en/get-diagnostics.html
GET [CURRENT | STACKED] DIAGNOSTICS { statement_information_item [, statement_information_item] ... (You can also use SHOW WARNINGS or SHOW ERRORS to see conditions or errors.) No special privileges are required to execute GET DIAGNOSTICS. The ...
https://dev.mysql.com/doc/refman/8.4/en/gis-format-conversion-functions.html
MySQL supports the functions listed in this section for converting geometry values from internal geometry format to WKT or WKB format, or for swapping the order of X and Y coordinates. There are also functions to convert a string from WKT or WKB ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-introduction.html
INFORMATION_SCHEMA provides access to database metadata, information about the MySQL server such as the name of a database or table, the data type of a column, or access privileges. Other terms that are sometimes used for this information are data ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-information-schema-metrics-table.html
The INNODB_METRICS table provides information about InnoDB performance and resource-related counters. SET GLOBAL innodb_monitor_disable = [counter-name|module_name|pattern|all]; innodb_monitor_reset: Resets counter values to zero. SET GLOBAL ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-undo-tablespaces.html
Undo tablespaces contain undo logs, which are collections of records containing information about how to undo the latest change by a transaction to a clustered index record. Default undo tablespaces are created at initialization time to provide a ...
https://dev.mysql.com/doc/refman/8.4/en/is-null-optimization.html
MySQL can perform the same optimization on col_name IS NULL that it can use for col_name = constant_value. For example, MySQL can use indexes and ranges to search for NULL with IS NULL. This optimization does not occur in cases when the column ...
https://dev.mysql.com/doc/refman/8.4/en/known-issues.html
This section lists known issues in recent versions of MySQL. For information about platform-specific issues, see the installation and debugging instructions in Section 2.1, “General Installation Guidance”, and Section 7.9, “Debugging MySQL”. The following problems are known: Subquery optimization for IN is not as effective as for ...