Mysql Left() Or Substring()?

Both of these queries will produce same result. But which one is better, faster. SELECT LEFT(textField, 100) AS first100Chars SELECT SUBSTRING(textField, 1, 100 ) Thanks.

Solution 1:

By itself there is little difference, however left can potentially utilize an index while substring cannot.

Solution 2:

Substring will take little more time than left function. Though your case is straight forward use left function only.