SQL Select Distinct

The SQL SELECT DISTINCT Statement

The SELECT DISTINCT statement is used to return only distinct (unique) values.

In a table, a column may contain several duplicate values - and sometimes you want to list only the unique values.

Example

SELECT DISTINCT Country FROM Customers;

SELECT DISTINCT Syntax

<p><code class="sqlHigh">
 SELECT DISTINCT <em>column1</em>,<em> column2, ...</em><br/>
 FROM <em>table_name</em>;
</code></p>

Demo Database

Below is a selection from the Customers table used in the examples:

SELECT Example Without DISTINCT

If you omit the DISTINCT keyword, the SQL statement returns the "Country" value from all the records of the "Customers" table:

Example

SELECT Country FROM Customers;

Count Distinct Values

By using the COUNT() function with the DISTINCT keyword, we can count the number of unique countries.

Example

SELECT COUNT(DISTINCT Country) FROM Customers;

Note: The COUNT(DISTINCT column_name) is not supported in Microsoft Access databases.

Here is a workaround for MS Access:

Example

  SELECT Count(*) AS DistinctCountries
FROM (SELECT DISTINCT Country FROM Customers);

You will learn more about the COUNT() function later in this tutorial.