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https://dev.mysql.com/doc/refman/8.4/en/charset-collation-implementations.html
MySQL implements several types of collations: Simple collations for 8-bit character sets This kind of collation is implemented using an array of 256 weights that defines a one-to-one mapping from character codes to weights. It is a case-insensitive ...
https://dev.mysql.com/doc/refman/8.4/en/charset-repertoire.html
The repertoire of a character set is the collection of characters in the set. String expressions have a repertoire attribute, which can have two values: ASCII: The expression can contain only ASCII characters; that is, characters in the Unicode ...
https://dev.mysql.com/doc/refman/8.4/en/charset-table.html
The CREATE TABLE and ALTER TABLE statements have optional clauses for specifying the table character set and collation: CREATE TABLE tbl_name (column_list) [[DEFAULT] CHARACTER SET charset_name] [COLLATE collation_name]] ALTER TABLE tbl_name ...
https://dev.mysql.com/doc/refman/8.4/en/charset-unicode-conversion.html
Tables created with these row formats enable you to index a maximum of 1024 or 768 characters for utf8mb3 or utf8mb4 columns, respectively. The older server sees utf8 in the dump file object definitions and create new objects that use the (3-byte) ... This section describes issues that you may face when converting character data between the utf8mb3 and utf8mb4 character ...
https://dev.mysql.com/doc/refman/8.4/en/checksum-table.html
This row-by-row calculation is what you get with the EXTENDED clause, with InnoDB and all other storage engines other than MyISAM, and with MyISAM tables not created with the CHECKSUM=1 clause. For MyISAM tables created with the CHECKSUM=1 clause, ...[QUICK | EXTENDED] CHECKSUM TABLE reports a checksum for the contents of a ...
https://dev.mysql.com/doc/refman/8.4/en/constraint-foreign-key.html
MySQL supports ON UPDATE and ON DELETE foreign key references in CREATE TABLE and ALTER TABLE statements. MySQL requires that foreign key columns be indexed; if you create a table with a foreign key constraint but no index on a given column, an ...
https://dev.mysql.com/doc/refman/8.4/en/data-dictionary-schema.html
If an upgrade is necessary and supported, the server creates data dictionary tables with updated definitions, copies persisted metadata to the new tables, atomically replaces the old tables with the new ones, and reinitializes the data dictionary.
https://dev.mysql.com/doc/refman/8.4/en/drop-function-loadable.html
(DROP FUNCTION is also used to drop stored functions; see Section 15.1.29, “DROP PROCEDURE and DROP FUNCTION Statements”.) DROP FUNCTION is the complement of CREATE FUNCTION. DROP FUNCTION also removes the function from the Performance Schema ...
https://dev.mysql.com/doc/refman/8.4/en/error-log-components.html
Provides a parser for reading error log files created by previous server instances. Provides a parser for reading error log files created by previous server instances. Does not provide a parser for reading error log files created by previous server ... This section describes the characteristics of individual error log ...
https://dev.mysql.com/doc/refman/8.4/en/example-storage-engine.html
The EXAMPLE storage engine is a stub engine that does nothing. Its purpose is to serve as an example in the MySQL source code that illustrates how to begin writing new storage engines. To enable the EXAMPLE storage engine if you build MySQL from ...