Set Operators

Set operators combine the results of two component queries into a single result. Queries containing set operators are called compound queries. Table 4-5 lists the SQL set operators. They are fully described with examples in The Set Operators.

Table 5 Set Operators

Operator	Returns
UNION	All distinct rows selected by either query
UNION ALL	All rows selected by either query, including duplicates
INTERSECT	All distinct rows selected by both queries
INTERSECT ALL	All rows selected by both queries including duplicates
MINUS	All distinct rows selected by the first query but not the second
MINUS ALL	All rows selected by the first query but not the second including duplicates
EXCEPT	All distinct rows selected by the first query but not the second
EXCEPT ALL	All rows selected by the first query but not the second including duplicates