Left join
Also written: LEFT JOIN
A join that keeps every row of the first (left) table, filling the right table's columns with NULL where there's no match. Adding `WHERE right.key IS NULL` finds rows with no match.
Also written: LEFT JOIN
A join that keeps every row of the first (left) table, filling the right table's columns with NULL where there's no match. Adding `WHERE right.key IS NULL` finds rows with no match.