The SQL SELECT DISTINCT Statement


The SQL SELECT DISTINCT Statement

In a table, some of the columns may contain duplicate values. This is not a problem, however, sometimes you will want to list only the different (distinct) values in a table.

The DISTINCT keyword can be used to return only distinct (different) values.

SQL SELECT DISTINCT Syntax

SELECT DISTINCT column_name(s)
FROM table_name

SELECT DISTINCT Example

The "student" table:

Student _No
Student_Name
Address
Year_Study
Sex
Date_of_birth
Course_No
ST100
K.Ranjan
Kandy
1
Male
17/01/1988
C1
ST101
N.Kumanan
Jaffna
2
Male
15/12/1989
C2
ST102
S.Ranjini
Vavuniya
1
Female
17/01/1989
C1
ST103
K.Dias
Colombo
3
Male
22/07/1987
C1
ST104
A.Kavitha
Matara
3
Female
20/03/1985
C2
ST105
L.Lavanya
Galle
2
Female
22/04/1989
C2
ST106
G.Moorthy
Jaffna
2
Male
12/01/1986
C1
ST107
F.Nathan
Matara
2
Male
29/01/1990
C3
ST108
A.H.M.Akmal
Puttalam
1
Male
12/12/1990
C3

Now we want to select only the distinct values from the column named "Address" from the table above.

We use the following SELECT statement:

 SELECT DISTINCT Address FROM student;

The result-set will look like this:
+----------+
| Address |
| Kandy |
+----------+ | Jaffna |
| Matara |
| Vavuniya | | Colombo | | Galle | | Puttalam | +----------+

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