SQL SELECT DISTINCT Statement
This chapter will explain the 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
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SELECT DISTINCT Example
The "Persons" table:
P_Id |
LastName |
FirstName |
Address |
City |
1 |
Hansen |
Ola |
Timoteivn 10 |
Sandnes |
2 |
Svendson |
Tove |
Borgvn 23 |
Sandnes |
3 |
Pettersen |
Kari |
Storgt 20 |
Stavanger |
Now we want to select only the distinct values from the column named "City"
from the table above.
We use
the following SELECT
statement:
SELECT DISTINCT City FROM Persons
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The result-set will look like this:
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