Checking Whether a String Contains a Substring

Source: https://www.oreilly.com/library/view/mysql-cookbook/0596001452/ch04s06.html

Problem

You want to know whether a given string occurs within another string.

Solution

Use LOCATE( ).

Discussion

The LOCATE( ) function takes two arguments representing the substring that you’re looking for and the string in which to look for it. The return value is the position at which the substring occurs, or 0 if it’s not present. An optional third argument may be given to indicate the position within the string at which to start looking.

mysql> SELECT name, LOCATE('in',name), LOCATE('in',name,3) FROM metal;
+----------+-------------------+---------------------+
| name     | LOCATE('in',name) | LOCATE('in',name,3) |
+----------+-------------------+---------------------+
| copper   |                 0 |                   0 |
| gold     |                 0 |                   0 |
| iron     |                 0 |                   0 |
| lead     |                 0 |                   0 |
| mercury  |                 0 |                   0 |
| platinum |                 5 |                   5 |
| silver   |                 0 |                   0 |
| tin      |                 2 |                   0 |
+----------+-------------------+---------------------+

LOCATE( ) is not case sensitive as of MySQL 4.0.0, and is case sensitive before that.