QUOTE
Quotes a string to produce a result that can be used as a properly escaped data value in an SQL statement.
Syntax
QUOTE(<str>)
Examples
SELECT QUOTE('Don\'t!');
+-----------------+
| QUOTE('Don't!') |
+-----------------+
| Don\'t! |
+-----------------+
SELECT QUOTE(NULL);
+-------------+
| QUOTE(NULL) |
+-------------+
| NULL |
+-------------+