DISTINCT — Show Unique Values

In SQL, the DISTINCT keyword is used to return only unique (non-duplicate) values.
This is helpful when you want to see what values exist in a column, without listing the same value multiple times.

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Syntax

SELECT DISTINCT column1 FROM table_name;

Example: Unique Departments

SELECT DISTINCT department FROM employees;

This will return a list of unique department values from the employees table — for example, 'HR', 'IT', 'Sales', etc.

Use DISTINCT when you're more interested in what values exist, not how many times they appear.

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Advanced: DISTINCT with Multiple Columns

You can also use DISTINCT with more than one column:

SELECT DISTINCT column1, column2 FROM table_name;

This returns only the unique pairs of values from those two columns — meaning it will list each unique combination only once.

Example: Unique Department + Gender Combinations

SELECT DISTINCT department, gender FROM employees;

This gives you all unique combinations of department and gender across the table.