The SQL WHERE clause is used to filter records by adding it to an SQL statement – SQL Select, update, delete, insert statement.
SQL WHERE Syntax
SELECT * FROM TableName WHERE ColumnName operator Value
SQL WHERE Examples
Table: Employees
| EmployeeId | FirstName | LastName | Department | Salary |
|---|---|---|---|---|
| 203 | Mazojys | Fxoj | Finance | 78000 |
| 204 | Jozzh | Lnanyo | Finance | 45800 |
| 205 | Syllauu | Dfaafk | Finance | 57000 |
| 206 | Gecrrcc | Srlkrt | Finance | 62000 |
| 302 | Jssme | Bdnaa | Development | 75000 |
| 303 | Dnnaao | Errllov | Development | 55000 |
| 304 | Tyoysww | Osk | Development | 49000 |
The following are examples of different operators:
= (Equal)
SELECT * FROM Employees WHERE FirstName = 'Jssme'
<> (Not Equal)
SELECT * FROM Employees WHERE FirstName <> 'Jssme'
> (Greater than)
SELECT * FROM Employees WHERE Salary > 55000
< (Less than)
SELECT * FROM Employees WHERE Salary < 55000
>= (Greater than or equal)
SELECT * FROM Employees WHERE Salary >= 55000
<= (Less than or equal)
SELECT * FROM Employees WHERE Salary <= 55000
BETWEEN (Between a range)
SELECT * FROM Employees WHERE Salary BETWEEN 55000 AND 75000
LIKE (seach for a pattern)
SELECT * FROM Employees WHERE FirstName LIKE 'Jss%'
IN (In a value-set)
SELECT * FROM Employees WHERE EmployeeId IN (203, 204, 302)
We can also combine the operators together:
SELECT *
FROM Employees
WHERE (FirstName LIKE 'J%'
AND Salary > 55000
)
OR EmployeeId = 304