SQL WHERE Clause

The WHERE clause is used to filter records.

The SQL WHERE Clause

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

SQL WHERE Syntax

<div class="w3-code w3-border notranslate">
<div>SELECT <em>column_name</em>,<em>column_name</em>
FROM <em>table_name</em>
WHERE <em>column_name operator value</em>;</div>
<div>

Demo Database

In this tutorial we will use the well-known Northwind sample database.

Below is a selection from the “Customers” table:

CustomerID CustomerName ContactName Address City PostalCode Country
1 Alfreds Futterkiste Maria Anders Obere Str. 57 Berlin 12209 Germany
2 Ana Trujillo Emparedados y helados Ana Trujillo Avda. de la Constitución 2222 México D.F. 05021 Mexico
3 Antonio Moreno Taquería Antonio Moreno Mataderos 2312 México D.F. 05023 Mexico
4 Around the Horn Thomas Hardy 120 Hanover Sq. London WA1 1DP UK
5 Berglunds snabbköp Christina Berglund Berguvsvägen 8 Luleå S-958 22 Sweden

WHERE Clause Example

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

Example

<div class="w3-code notranslate">SELECT * FROM Customers
WHERE Country='Mexico';</div>

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

<div class="w3-code notranslate">SELECT * FROM Customers
WHERE CustomerID=1;</div>

Operators in The WHERE Clause

The following operators can be used in the WHERE clause:

Operator Description
= Equal
<> Not equal. Note: In some versions of SQL this operator may be written as !=
> Greater than
< Less than
>= Greater than or equal
<= Less than or equal
BETWEEN Between an inclusive range
LIKE Search for a pattern
IN To specify multiple possible values for a column
Pankaj Singh Sugara

Author Pankaj Singh Sugara

Experienced Software Engineer with a demonstrated history of working in the marketing and advertising industry. Skilled in SQL, Web Applications, PHP, WordPress, and Joomla. Strong engineering professional with a B-TECH focused in Information Technology from JCDM College of Engineering Sirsa, Haryana.

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