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Using the REPLACE Command

Another method for modifying records is to use the REPLACE command, which is remarkably similar to the INSERT command.

REPLACE INTO table_name (column list) VALUES (column values);

The REPLACE statement works like this: If the record you are inserting into the table contains a primary key value that matches a record already in the table, the record in the table will be deleted and the new record inserted in its place.

The REPLACE command is a MySQL-specific extension to ANSI SQL. This command mimics the action of a DELETE and re-INSERT of a particular record. In other words, you get two commands for the price of one. ...