Answer : Union All , Select
The UNION operator selects only distinct values by default. To allow duplicate values, use the ALL keyword with UNION.
INTERSECT command will only return distinct values.
Similar to the UNION command, INTERSECT also operates on two SQL statements. The difference is that, while UNION essentially acts as an OR operator (value is selected if it appears in either the first or the second statement), the INTERSECT command acts as an AND operator (value is selected only if it appears in both statements).
Reference : http://www.tutorialspoint.com/sql/sql-intersect-clause.htm
