group function which specifies that only one row will be returned for each unique value. For example, a select distinct on last name would return only one value for "Smith", even if there were 5 different Smiths in the warehouse.
(SQL) Optional clause of the SELECT statement. Use when the SELECT attributes do not form a super key of the FROM clause. multijoin.php
Ignores duplicates. SELECT DISTINCT grade FROM grade_report Might produce: a, b, c, d, f where SELECT grade would produce all the values in the table.