insert update delete in mysql with single query

Question

I have two table source and target. Is it possible to perform following operation in single query?

• If the row exists in both the source and target, UPDATE the target;

• If the row only exists in the source, INSERT the row into the target;

• If the row exists in the target but not the source,
  DELETE the row from the target.

Answer 1

You can't do it all in one query, but you can do it all in one transaction if you are using a transactional store engine (like InnoDB). This might be what you want,

START TRANSACTION;

INSERT...; DELETE... UPDATE...;

COMMIT;