SQL wildcards can be used when searching for data in a database.
SQL wildcards must be used with the SQL LIKE operator.
With SQL, the following wildcards can be used:
Wildcard | Description |
% | A substitute for zero or more characters |
_ | A substitute for exactly one character |
[charlist] | Any single character in charlist |
[^charlist] or[!charlist] | Any single character not in charlist |
SQL Wildcard Examples
We have the following "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 |
Using the % Wildcard
Now we want to select the persons living in a city that starts with "sa" from the "Persons" table.We use the following SELECT statement:
SELECT * FROM Persons WHERE City LIKE 'sa%' |
P_Id | LastName | FirstName | Address | City |
1 | Hansen | Ola | Timoteivn 10 | Sandnes |
2 | Svendson | Tove | Borgvn 23 | Sandnes |
We use the following SELECT statement:
SELECT * FROM Persons WHERE City LIKE '%nes%' |
P_Id | LastName | FirstName | Address | City |
1 | Hansen | Ola | Timoteivn 10 | Sandnes |
2 | Svendson | Tove | Borgvn 23 | Sandnes |
Using the _ Wildcard
Now we want to select the persons with a first name that starts with any character, followed by "la" from the "Persons" table.We use the following SELECT statement:
SELECT * FROM Persons WHERE FirstName LIKE '_la' |
P_Id | LastName | FirstName | Address | City |
1 | Hansen | Ola | Timoteivn 10 | Sandnes |
We use the following SELECT statement:
SELECT * FROM Persons WHERE LastName LIKE 'S_end_on' |
P_Id | LastName | FirstName | Address | City |
2 | Svendson | Tove | Borgvn 23 | Sandnes |
Using the [charlist] Wildcard
Now we want to select the persons with a last name that starts with "b" or "s" or "p" from the "Persons" table.We use the following SELECT statement:
SELECT * FROM Persons WHERE LastName LIKE '[bsp]%' |
P_Id | LastName | FirstName | Address | City |
2 | Svendson | Tove | Borgvn 23 | Sandnes |
3 | Pettersen | Kari | Storgt 20 | Stavanger |
We use the following SELECT statement:
SELECT * FROM Persons WHERE LastName LIKE '[!bsp]%' |
P_Id | LastName | FirstName | Address | City |
1 | Hansen | Ola | Timoteivn 10 | Sandnes |
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