The SQL DISTINCT clause is used together with the SQL SELECT keyword, to return a dataset with unique entries for certain database table column.
We will use our Customers database table to illustrate the usage of SQL DISTINCT.
FirstName LastName Email DOB Phone
John Smith John.Smith@yahoo.com 2/4/1968 626 222-2222
Steven Goldfish goldfish@fishhere.net 4/4/1974 323 455-4545
Paula Brown pb@herowndomain.org 5/24/1978 416 323-3232
James Smith jim@supergig.co.uk 20/10/1980 416 323-8888
For example if we want to select all distinct surnames from our Customers table, we will use the following SQL DISTINCT statement:
SELECT DISTINCT LastName
FROM Customers
The result of the SQL DISTINCT expression above will look like this:
LastName
Smith
Goldfish
Brown
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