Syntax
LENGTH(str)
Purpose
You can call this function to return the length of str in bytes.
A multi-byte character is counted as multiple characters. For example, if you enter five two-byte characters, CHAR_LENGTH() returns 5, while LENGTH() returns 10.
Examples
obclient> SELECT LENGTH('hi'), LENGTH('hello');
+--------------+-----------------+
| LENGTH('hi') | LENGTH('hello') |
+--------------+-----------------+
| 2 | 5 |
+--------------+-----------------+
1 row in set