Name the type of join used to include rows that do not have matching values
Answer options
A
Cartesian product
B
inner join
C
non equi-join
D
outer join
Correct answer: outer join
Explanation
An outer join (LEFT, RIGHT, or FULL OUTER JOIN) includes rows from one or both tables that do not have matching values in the other table, filling unmatched columns with NULL. Inner join returns only matching rows; Cartesian product returns all combinations; non equi-join uses a non-equality condition but still requires some relationship.