# LENGTHB

## Syntax

```sql
LENGTHB(str)
```

## Description

`LENGTHB()` returns the length of the given string, in bytes. When [Oracle mode](https://app.gitbook.com/s/aEnK0ZXmUbJzqQrTjFyb/community-server/about/compatibility-and-differences/sql_modeoracle) is not set, this is a synonym for [LENGTH](https://mariadb.com/docs/server/reference/sql-functions/string-functions/length).

A multi-byte character counts as multiple bytes. This means that for a string containing five two-byte characters, `LENGTHB()` returns 10, whereas [CHAR\_LENGTH()](https://mariadb.com/docs/server/reference/sql-functions/string-functions/char_length) returns 5.

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

## Examples

When Oracle mode is not set:

```sql
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:

```sql
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()](https://mariadb.com/docs/server/reference/sql-functions/string-functions/char_length)
* [LENGTH()](https://mariadb.com/docs/server/reference/sql-functions/string-functions/length)
* [OCTET\_LENGTH()](https://mariadb.com/docs/server/reference/sql-functions/string-functions/octet_length)

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