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https://dev.mysql.com/doc/refman/9.7/en/ansi-diff-foreign-keys.html
For example, if you define a RESTRICT type constraint, and there is a child row with several parent rows, InnoDB does not permit the deletion of any of the parent rows. This means that you cannot use self-referential ON UPDATE CASCADE or ON UPDATE ...
https://dev.mysql.com/doc/refman/9.7/en/charset-conversion.html
Note ALTER TABLE statements which make changes in table or column character sets or collations must be performed using ALGORITHM=COPY. To convert a binary or nonbinary string column to use a particular character set, use ALTER TABLE. For successful ...
https://dev.mysql.com/doc/refman/9.7/en/charset-errors.html
For more information about character_set_results, see Section 12.4, “Connection Character Sets and Collations”. This section describes how the MySQL server uses character sets for constructing error messages. For information about the language ...
https://dev.mysql.com/doc/refman/9.7/en/charset-restrictions.html
In addition, these operators compare characters by their byte values and accented characters may not compare as equal even if a given collation treats them as equal. Identifiers are stored in mysql database tables (user, db, and so forth) using ...
https://dev.mysql.com/doc/refman/9.7/en/check-table.html
Changes are sometimes made to character sets or collations that require table indexes to be rebuilt. option: { FOR UPGRADE | QUICK | FAST | MEDIUM | EXTENDED | CHANGED } CHECK TABLE checks a table or tables for errors. CHECK TABLE can also check ...
https://dev.mysql.com/doc/refman/9.7/en/create-table-check-constraints.html
CREATE TABLE permits the core features of table and column CHECK constraints, for all storage engines. CREATE TABLE permits the following CHECK constraint syntax, for both table constraints and column constraints: [CONSTRAINT [symbol]] CHECK (expr) ...
https://dev.mysql.com/doc/refman/9.7/en/create-table-select.html
Retrained attributes are NULL (or NOT NULL) and, for those columns that have them, CHARACTER SET, COLLATION, COMMENT, and the DEFAULT clause. You can create one table from another by adding a SELECT statement at the end of the CREATE TABLE ...
https://dev.mysql.com/doc/refman/9.7/en/data-dictionary-information-schema.html
In particular, for each INFORMATION_SCHEMA table that is a view on data dictionary tables: The server no longer must create a temporary table for each query of the INFORMATION_SCHEMA table. When the underlying data dictionary tables store values ...
https://dev.mysql.com/doc/refman/9.7/en/date-and-time-functions.html
DATE_FORMAT() returns a string with a character set and collation given by character_set_connection and collation_connection so that it can return month and weekday names containing non-ASCII characters. This section describes the functions that ...
https://dev.mysql.com/doc/refman/9.7/en/engine-condition-pushdown-optimization.html
A string value to be compared with a column must use the same collation as the column. This optimization improves the efficiency of direct comparisons between a nonindexed column and a constant. In such cases, the condition is “pushed down” to ...