SQL WHERE Clause

The SQL WHERE Clause

Table of Contents

What is the WHERE Clause?

The WHERE clause is used to filter records in SQL queries. It is used to extract only those records that satisfy a specific condition.

Select all customers from Mexico:

SELECT * FROM Customers
WHERE Country = 'Mexico';

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

Note: The WHERE clause can be used not only in SELECT statements but also in UPDATE, DELETE, and other SQL statements.

Below is a selection from the “Customers” table used in the examples:

CustomerID	CustomerName	ContactName	Country
1	Alfreds Futterkiste	Maria Anders	Germany
2	Ana Trujillo	Ana Trujillo	Mexico

SQL requires single quotes around text values (e.g., ‘Mexico’), but numeric fields should not be enclosed in quotes.

SELECT * FROM Customers
WHERE CustomerID = 1;

You can use various operators in the WHERE clause to filter records: