MySQL WHERE Clause

The MySQL WHERE Clause

The WHERE clause is used to filter records.

It 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 statements, it is also used in UPDATE, DELETE, etc.!

Demo Database

Below is a selection from the “Customers” table in the Northwind sample database:

WHERE Clause Example

The following SQL statement selects all the customers from “Mexico”:

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: