Explain UNION,MINUS,UNION ALL, INTERSECT ?

Explain UNION,MINUS,UNION ALL, INTERSECT ?
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1 Answer

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