MySQL :: MySQL 3.23, 4.0, 4.1 Reference Manual :: 12.2.9 UPDATE Syntax

Update column in a table whose values are not found in another table. UPDATE TABLE_1 LEFT JOIN TABLE_2 ON TABLE_1.COLUMN_1= TABLE_2.COLUMN_2 SET TABLE_1.COLUMN = EXPR WHERE TABLE_2.COLUMN2 IS NULL An outerjoin is performed ...

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