INTERSECT

SQL: SELECT: Joins and Sets

Returns only values that are in both data sets. Example:

// Get list of classes offered in both schools.

SELECT evening_class FROM school_1 
    INTERSECT 
SELECT evening_class FROM school_2
        ORDER BY evening_class ASC;

//Get list of restaurants at both mall locations.

SELECT store FROM mall_south WHERE type = "restaurant"
        INTERSECT 
SELECT store FROM mall_north WHERE type = "restaurant";