The 1-based lines in code (comment-stripped) that open an existence guard. IF EXISTS over ordinary data — "if any row still has the old value, update it" — is not a guard and is left alone.
code
IF EXISTS
The 1-based lines in
code(comment-stripped) that open an existence guard.IF EXISTSover ordinary data — "if any row still has the old value, update it" — is not a guard and is left alone.