SQL SELECT DISTINCT Statement

-- select the unique ages from the Customers table
SELECT DISTINCT age
FROM Customers;

SQL DISTINCT Syntax

The syntax of the SQL DISTINCT statement is:

SELECT DISTINCT column1, column2 ...
FROM table;

Here,

• column1, column2, ... are the table columns
• table is the table name from where we retrieve the distinct columns

For example,

-- select the unique countries from the customers table
SELECT DISTINCT country
FROM Customers;

Here, the SQL command selects unique countries from the Customers table.

SQL DISTINCT With Multiple Columns

We can also use SELECT DISTINCT with multiple columns.

For example,

-- select rows if the first name and country of a customer is unique
SELECT DISTINCT country, first_name
FROM Customers;

Here, the SQL command selects rows if the combination of country and first_name is unique.

DISTINCT With COUNT

If we need to count the number of unique rows, we can use the COUNT() function with DISTINCT.

-- count the unique countries where customers are from 
SELECT COUNT(DISTINCT country)
FROM Customers;

Here, the SQL command returns the count of unique countries.

To learn more, visit SQL COUNT().

-- with distinct
SELECT DISTINCT country
FROM Customers;

-- with group by
SELECT country
FROM Customers
GROUP BY country;

-- with order by
SELECT DISTINCT age
FROM Customers
ORDER BY age DESC;