LENGTH

Return the length of a string in bytes. This function counts the number of bytes in the string, which may differ from character count for multi-byte strings.

Syntax

LENGTH(str)

Description

Returns the length of the string str.

In the default mode, when Oracle mode is not set, the length is measured in bytes. In this case, a multi-byte character counts as multiple bytes. LENGTH() returns the length in bytes, whereas CHAR_LENGTH() returns the number of characters. This means that, for a string containing five two-byte characters, LENGTH() returns 10, whereas CHAR_LENGTH() returns 5. When running Oracle mode, the length is measured in characters, and LENGTH is a synonym for CHAR_LENGTH().

If str is not a string value, it is converted into a string. If str is NULL, the function returns NULL.

Examples

SELECT LENGTH('MariaDB');
+-------------------+
| LENGTH('MariaDB') |
+-------------------+
|                 7 |
+-------------------+

When Oracle mode is not set:

SELECT CHAR_LENGTH('π'), LENGTH('π'), LENGTHB('π'), OCTET_LENGTH('π');
+-------------------+--------------+---------------+--------------------+
| CHAR_LENGTH('π')  | LENGTH('π')  | LENGTHB('π')  | OCTET_LENGTH('π')  |
+-------------------+--------------+---------------+--------------------+
|                 1 |            2 |             2 |                  2 |
+-------------------+--------------+---------------+--------------------+

In Oracle mode:

SELECT CHAR_LENGTH('π'), LENGTH('π'), LENGTHB('π'), OCTET_LENGTH('π');
+-------------------+--------------+---------------+--------------------+
| CHAR_LENGTH('π')  | LENGTH('π')  | LENGTHB('π')  | OCTET_LENGTH('π')  |
+-------------------+--------------+---------------+--------------------+
|                 1 |            1 |             2 |                  2 |
+-------------------+--------------+---------------+--------------------+

See Also

• CHAR_LENGTH()

• LENGTHB()

• OCTET_LENGTH()

• Oracle mode

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