MySQL LEFT() Function: Extract Characters from the Left of a String

Learn how to use the MySQL `LEFT()` function to efficiently extract a specified number of characters from the beginning of a string. This guide explains the function's syntax, provides practical examples, and demonstrates how to use `LEFT()` for effective text manipulation in your MySQL queries.

MySQL LEFT() Function

Definition and Usage

The LEFT() function in MySQL extracts a specified number of characters from the beginning (left side) of a string. It's a handy function for working with text data.

Syntax


LEFT(string, number_of_chars)

Parameter Values

Parameter	Description
`string`	Required. The string from which you want to extract characters.
`number_of_chars`	Required. The number of characters to extract from the left. If this number is larger than the string's length, the entire string is returned.

Examples

Example 1: Extracting Characters from a Literal String

This example extracts the first three characters from the string "SQL Tutorial".

SQL Query


SELECT LEFT("SQL Tutorial", 3) AS ExtractString;

Output


ExtractString
-------------
SQL

Example 2: Extracting Characters from a Column

This example shows how to extract the first 5 characters from the "CustomerName" column in a "Customers" table.

SQL Query


SELECT LEFT(CustomerName, 5) AS ExtractString FROM Customers;

Output


(This output will vary depending on the data in the Customers table. It will show the first 5 characters of each CustomerName.)

Technical Details

The LEFT() function has been available in MySQL since version 4.0.

Tip

For extracting characters from the right side of a string, see the RIGHT() function.