Syntax
------ 
CHAR_LENGTH(str)
 
Description
----------- 
Returns the length of the given string argument, measured in
characters. A multi-byte character counts as a single
character. This means that for a string containing five
two-byte characters, LENGTH() (or OCTET_LENGTH() in Oracle
mode) returns 10, whereas CHAR_LENGTH() returns 5. If the
argument is NULL, it returns NULL. 
 
If the argument is not a string value, it is converted into
a string.
 
It is synonymous with the CHARACTER_LENGTH() function.
 
Until MariaDB 10.3.1, returns MYSQL_TYPE_LONGLONG, or
bigint(10), in all cases. From MariaDB 10.3.1, returns
MYSQL_TYPE_LONG, or int(10), when the result would fit
within 32-bits.
 
Examples
-------- 
SELECT CHAR_LENGTH('MariaDB');
+------------------------+
| CHAR_LENGTH('MariaDB') |
+------------------------+
| 7 |
+------------------------+
 
SELECT CHAR_LENGTH('π');
+-------------------+
| CHAR_LENGTH('π') |
+-------------------+
| 1 |
+-------------------+
 


URL: https://mariadb.com/kb/en/char_length/