SQL SELECT DISTINCT

The SQL SELECT DISTINCT statement is used to select distinct(different, unique) value of centain database table column(s), and remove the duplicates from the result. The usage of this statement is same among MS SQL Server, Oracle, MySQL.

SQL SELECT DISTINCT Syntax

SELECT DISTINCT Column1, Column2, ...
FROM Table

SQL SELECT DISTINCT Example

Table: Employees

EmployeeId FirstName LastName Department Salary
203 Mary Fox Finance 78000
204 Joe Lanyon Finance 45800
205 Sally Daff Finance 57000
206 Grace Salter Finance 62000
302 James Fox Development 75000
303 Dona Lanyon Development 55000
304 Tony Oakes Development 49000

Select all the unique last names without duplicates:

SELECT DISTINCT LastName
FROM Employees

The result of above statement will look like:

LastName
Fox
Lanyon
Daff
Salter
Oakes

The DISTINCT clause can be used with more than one column:

SELECT DISTINCT FirstName, LastName
FROM Employees

The above statement will return each unique FirstName and LastName combination. The result of this statement will look like:

FirstName LastName
Mary Fox
Joe Lanyon
Sally Daff
Grace Salter
James Fox
Dona Lanyon
Tony Oakes

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