A FIRST clause

You can use the FIRST clause to select the first rows that result from a union query. The following query uses a FIRST clause to return the first five rows of a union between the stock and items tables.
Figure 1: Query
SELECT FIRST 5 DISTINCT stock_num, manu_code
   FROM stock
   WHERE unit_price < 55.00
UNION 
SELECT stock_num, manu_code
   FROM items
   WHERE quantity > 3;
Figure 2: Query result
stock_num manu_code

        5 NRG 
        5 ANZ
        6 SMT
        6 ANZ
        9 ANZ