Performance question: ON DUPLICATE KEY UPDATE vs UPDATE (MySQL) -


is there performance difference between insert on duplicate key update , update?

if know values can updated - should use update or not matter?

there difference.

the insert query has check constraints on every column see if they're violated adding row. if so, needs find matching row update , perform update.

an update query has find row update , perform update.

if know row exists, should update it.


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