Search Results
https://dev.mysql.com/doc/refman/9.7/en/constraint-enum.html
Errors for invalid values can be suppressed in strict mode if you use INSERT IGNORE or UPDATE IGNORE. For ENUM, the value is inserted as the error member (0). For SET, the value is inserted as given except that any invalid substrings are deleted.
https://dev.mysql.com/doc/refman/9.7/en/create-table-check-constraints.html
CHECK constraints are evaluated for INSERT, UPDATE, REPLACE, LOAD DATA, and LOAD XML statements and an error occurs if a constraint evaluates to FALSE. CHECK constraints are evaluated for INSERT IGNORE, UPDATE IGNORE, LOAD DATA ... CREATE TABLE ...
https://dev.mysql.com/doc/refman/9.7/en/create-table-foreign-keys.html
For storage engines that support foreign keys, MySQL rejects any INSERT or UPDATE operation that attempts to create a foreign key value in a child table if there is no matching candidate key value in the parent table. MySQL supports foreign keys, ...
https://dev.mysql.com/doc/refman/9.7/en/create-user.html
To use CREATE USER, you must have the global CREATE USER privilege, or the INSERT privilege for the mysql system schema. This query displays the row in this table inserted by the statement just shown for creating the user jim@localhost: mysql> ...
https://dev.mysql.com/doc/refman/9.7/en/data-change-optimization.html
This section explains how to speed up data change statements: INSERT, UPDATE, and DELETE. For inserting and updating large volumes of data (known in the industry as ETL, for “extract-transform-load”), sometimes you use other SQL statements or ...Traditional OLTP applications and modern web applications typically do many small data change operations, where concurrency is ...
https://dev.mysql.com/doc/refman/9.7/en/declare-handler.html
HANDLER statement had not been present, MySQL would have taken the default action (EXIT) after the second INSERT failed due to the PRIMARY KEY constraint, and SELECT @x would have returned 2. statement handler_action: { CONTINUE | EXIT | UNDO } ...
https://dev.mysql.com/doc/refman/9.7/en/derived-tables.html
For information about lateral derived tables preceded by the LATERAL keyword, see Section 15.2.15.9, “Lateral Derived Tables”. A derived table is an expression that generates a table within the scope of a query FROM clause. For example, a ...
https://dev.mysql.com/doc/refman/9.7/en/explain.html
Obtaining Execution Plan Information The EXPLAIN statement provides information about how MySQL executes statements: EXPLAIN works with SELECT, DELETE, INSERT, REPLACE, UPDATE, and TABLE statements. In practice, the DESCRIBE keyword is more often ...
https://dev.mysql.com/doc/refman/9.7/en/faqs-innodb-change-buffer.html
What types of operations modify secondary indexes and result in change buffering? INSERT, UPDATE, and DELETE operations can modify secondary indexes. How do I determine the current size of the change buffer? The current size of the change buffer is ...What types of operations modify secondary indexes and result in change buffering? ...
https://dev.mysql.com/doc/refman/9.7/en/fulltext-restrictions.html
For InnoDB, all DML operations (INSERT, UPDATE, DELETE) involving columns with full-text indexes are processed at transaction commit time. For example, for an INSERT operation, an inserted string is tokenized and decomposed into individual words.