MySQL LEFT() Function

The LEFT() function in MySQL returns a specific number of characters from the start (left side) of a string.

MySQL LEFT Function Syntax

LEFT(string, number_of_chars)

MySQL LEFT Function Example

This query extracts the first 3 characters from the string “SQL Tutorial”:

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

Note: This example works in MySQL, but does not work in SQLite or the TechKubo Playground.

MySQL LEFT Function Parameters

MySQL LEFT Function Patients Table Example

This query attempts to extract the first 2 characters from each first_name in the Patients table:

SELECT LEFT(first_name, 2) AS Initials
FROM Patients;

Note: This example works in MySQL, but does not work in SQLite or the TechKubo Playground.

MySQL LEFT Function Notes

• If the number of characters is greater than the string length, the whole string is returned.
• In SQLite (including TechKubo), use SUBSTR(column, 1, N) instead of LEFT().
• Available in MySQL 4.0 and later.