SQL DISTINCT usage

Usage

Allows you to use the DISTINCT keyword to eliminate duplicate rows of query results. Different is very useful query, you just want to know whether there is a value table, and not how many times interested. The different itself can only be used once in the SELECT statement. However, you can specify a distinct number of columns. In this case, the SQL will eliminate those rows, where the values are in all the same columns.

The syntax for the DISTINCT clause is:

SELECT DISTINCT column_name
From derived_table
WHERE conditions

Instance One

SELECT DISTINCT Ownerlastname
From Antiqueowners

A lastnames, you have the last name table, ' Jones, repeated many times. This code returns only one ' Jones '.
SELECT DISTINCT City,state
From employeeaddresstable