Where a Key value exists in several rows, a second key must be used to avoid accidental deletions.
Note: SYNC commands trigger a COMPARE in order to determine which objects are to be SYNCed.
Compare Table A and B using ID as unique key.
COMPARE A to B using KEY ID
Rows with Name “house” are matched.
Rows with Name “car” are not matched and flagged for deletion.
In this case, the appropriate key is (id, name).