SQL WHERE Clause

The SQL WHERE Clause

The WHERE clause is used to filter records.

The WHERE clause is used to extract only those records that fulfill a specified condition.

WHERE Syntax

SELECT column1, column2, ...
FROM table_name
WHERE condition;

Note: The WHERE clause is not only used in SELECT statement, it is also used in UPDATE, DELETE statement, etc.!

Demo Database

Below is a selection from the "Customers" table in a sample database:

WHERE Clause Example

The following SQL statement selects all the customers from the country "Mexico", in the "Customers" table:

Example
SELECT * FROM Customers
WHERE Country='Mexico';

Text Fields vs. Numeric Fields

SQL requires single quotes around text values (most database systems will also allow double quotes).

However, numeric fields should not be enclosed in quotes:Example

SELECT * FROM Customers
WHERE CustomerID=1;

Operators in The WHERE Clause

The following operators can be used in the WHERE clause: