Syntax
LENGTH(str)
Purpose
LENGTH() returns 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 ('OceanBase'), LENGTH('hello');
+----------------------+-----------------+
| LENGTH ('OceanBase') | LENGTH('hello') |
+----------------------+-----------------+
| 9 | 5 |
+----------------------+-----------------+
1 row in set