Materialize/doc/user/content/sql/functions/length.md

---

title: "LENGTH function" description: "Returns the number of characters in a string." menu: main:

parent: 'sql-functions'

---

LENGTH returns the code points in an encoded string.

Signatures

{{< diagram "func-length.svg" >}}

Parameter	Type	Description
str	string or bytea	The string whose length you want.
encoding_name	string	The encoding you want to use for calculating the string's length. Defaults to UTF-8.

Return value

length returns an int.

Details

Errors

length operations might return NULL values indicating errors in the following cases:

• The encoding_name provided is not available in our encoding package.
• Some byte sequence in str was not compatible with the selected encoding.

Encoding details

• Materialize uses the encoding crate. See the list of supported encodings, as well as their names within the API.

• Materialize attempts to convert PostgreSQL-style encoding names into the WHATWG-style encoding names used by the API.

  For example, you can refer to iso-8859-5 (WHATWG-style) as ISO_8859_5 (PostrgreSQL-style).

  However, there are some differences in the names of the same encodings that we do not convert. For example, the windows-874 encoding is referred to as WIN874 in PostgreSQL; Materialize does not convert these names.

Examples

SELECT length('你好') AS len;

 len
-----
   2

---

SELECT length('你好', 'big5') AS len;

 len
-----
   3