SQL WHERE Clause

The SQL WHERE clause is used to filter records from a database table. It is an important part of any SQL query and is commonly used to specify which rows to include or exclude in the result set. WHERE is a powerful operation and can be used to select only the rows that meet certain conditions, such as matching a specific value or range of values.

Syntax

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

Example

SELECT *
FROM customers
WHERE city = 'New York';
    

This example selects all columns and rows from the "customers" table where the city is 'New York'.

Operators

• =: Equal to
• >: Greater than
• <: Less than
• >=: Greater than or equal to
• <=: Less than or equal to
• <>: Not equal to
• BETWEEN: Between a certain range of values
• LIKE: Search for a specific pattern
• IN: Matches any of a list of values
• IS NULL: Is a null value

You can use these operators in combination with AND, OR, and parentheses to create complex conditions. For example:

SELECT * FROM customers WHERE city = 'New York' AND (age >= 30 AND age <= 50)

You can learn more about these and other advanced topics in our SQL tutorials and references.