Explain Union, Minus, Union All, Intersect ?

1.	Explain Union, Minus, Union All, Intersect ?
Answer» INTERSECT - returns all distinct ROWS SELECTED by both QUERIES. MINUS - returns all distinct rows selected by the first query but not by the second. UNION - returns all distinct rows selected by either query. UNION ALL - returns all rows selected by either query, including all duplicates. INTERSECT - returns all distinct rows selected by both queries. MINUS - returns all distinct rows selected by the first query but not by the second. UNION - returns all distinct rows selected by either query. UNION ALL - returns all rows selected by either query, including all duplicates.

Answer»

INTERSECT - returns all distinct ROWS SELECTED by both QUERIES.

MINUS - returns all distinct rows selected by the first query but not by the second.

UNION - returns all distinct rows selected by either query.

UNION ALL - returns all rows selected by either query, including all duplicates.

INTERSECT - returns all distinct rows selected by both queries.

MINUS - returns all distinct rows selected by the first query but not by the second.

UNION - returns all distinct rows selected by either query.

UNION ALL - returns all rows selected by either query, including all duplicates.

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