Set Operators

Set operators combine the results of two component queries into a single result. Queries containing set operators are called compound queries. Table 3-4 lists SQL set operators. They are fully described, including restrictions on these operators, in "The UNION [ALL], INTERSECT, MINUS Operators".

Table 3-4  Set Operators

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