SQL DISTINCT


David Haertzen David Haertzen, Tutorial Author
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SQL > SQL Advanced > SQL DISTINCT


What is SQL DISTINCT?

SQL DISTINCT is a SQL keyword that specifies that only distinct / non-duplicate results are to be returned.

DISTINCT can apply to single columns or to multiple columns.

Why Use SQL DISTINCT?

The DISTINCT keyword can help to understand information. For example, a query containing DISTINCT could return a non-duplicated list of cities where a company does business.

How To Use SQL DISTINCT

SQL DISTINCT is used as follows.

SQL DISTINCT Syntax

 
SELECT DISTINCT <column_name>
FROM <table_name>
 

The word DISTINCT can be placed in front of a single column name or a number of column names. When in front of multiple column names, a distinct combination is returned.

SQL DISTINCT Example

The following example a DISTINCT list of region_nbr referenced in the branch table is returned.

Here are the contents of the table:

Table: BRANCH
branch_nbrbranch_nameregion_nbremployee_count
108New York10010
110Boston1006
212Chicago2005
404San Diego4006
415San Jose4003

This SQL Statement with DISTINCT is executed:

 
SELECT DISTINCT region_nbr
FROM branch
ORDER BY region_nbr
 

Here is the result.

region_nbr
100
200
400

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