Extended SET VAR Optimizer Hint¶

Percona Server for MySQL 8.0 extends the SET_VAR introduced in MySQL 8.0 effectively replacing the SET STATEMENT ... FOR statement. SET_VAR is an optimizer hint that can be applied to session variables.

Percona Server for MySQL 8.0 extends the SET_VAR hint to support the following:

• The OPTIMIZE TABLE statement
• MyISAM session variables
• Plugin or Storage Engine variables
• InnoDB Session variables
• The ALTER TABLE statement
• CALL stored_proc() statement
• The ANALYZE TABLE statement
• The CHECK TABLE statement
• The LOAD INDEX statement (used for MyISAM)
• The CREATE TABLE statement

Percona Server for MySQL 8.0 also supports setting the following variables by using SET_VAR: