Using SQL Distinct to Exclude Duplicates

Syntax of SQL SELECT DISTINCT

SELECT DISTINCT column1, column2, ...
FROM table_name;

Examples using a demo database

The Developers table

Theory is great, but we recommend digging deeper!

Microsoft SQL server 2019

Taurius Litvinavicius

5.0 (0)

Selecting all values from one column

SELECT City FROM Developers;

Selecting only distinct values from one column

SELECT DISTINCT City FROM Developers;

Counting distinct values

SELECT COUNT(DISTINCT City) FROM Developers;

Note: this example will not work in Microsoft Edge and Firefox, as they use Microsoft Access which doesn't support COUNT(DISTINCT column_name).

In MS Access

SELECT Count(*) AS DistinctCities
FROM (SELECT DISTINCT City FROM Developers);