SQL LIKE Keyword

The LIKE operator in SQL is used to search for a pattern within a column. It's incredibly useful for finding rows where a string column matches a specific pattern, allowing for flexible and efficient searches.

LIKE: Definition and Usage

LIKE is used within the WHERE clause of a SELECT statement (or other data retrieval statements). It uses wildcard characters to match patterns, making it much more powerful than a simple equality check.

Wildcard Characters

• %: Matches any sequence of zero or more characters.
• _: Matches any single character. (MS Access uses ? instead of _)

Syntax

SELECT column1, column2, ...
FROM table_name
WHERE column_name LIKE 'pattern';
      

Examples

Selecting Customers Whose Names Start with "a"

This query finds all customers whose names begin with the letter "a".

SELECT * FROM Customers
WHERE CustomerName LIKE 'a%';
      

(All rows where CustomerName starts with 'a' will be returned)
      

Selecting Customers Whose Names End with "a"

This query selects customers whose names end with "a".

SELECT * FROM Customers
WHERE CustomerName LIKE '%a';
      

(All rows where CustomerName ends with 'a' will be returned)
      

Selecting Customers Whose Names Contain "or"

This query finds customers with "or" anywhere in their name.

SELECT * FROM Customers
WHERE CustomerName LIKE '%or%';
      

(All rows where CustomerName contains 'or' will be returned)
      

Selecting Customers Whose Names Start with "a" and are at least 3 characters long

This query demonstrates using multiple wildcards. It finds names starting with 'a', followed by at least two more characters.

SELECT * FROM Customers
WHERE CustomerName LIKE 'a__%';
      

(All rows where CustomerName starts with 'a' and is at least 3 characters long will be returned)