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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