CHARACTER_LENGTH

Return the number of characters in the input string (alias of CHAR_LENGTH).

Category: stringReturns: INTEGERDialect: Standard

Syntax

CHARACTER_LENGTH(str)

Description

## Overview Returns the number of characters in the input string. CHARACTER_LENGTH is the full SQL-standard spelling of CHAR_LENGTH and is functionally identical to both CHAR_LENGTH and LENGTH on string inputs. Multi-byte UTF-8 characters count as one character each. This function exists for portability with SQL-standard code. In new code, CHAR_LENGTH and LENGTH are shorter equivalents. ## Behavior - Returns NULL when the input is NULL. - Returns 0 for an empty string. - Each Unicode code point counts as one character. - Combining sequences count as the number of code points, not grapheme clusters. - Trailing whitespace is counted; it is not trimmed implicitly. - Identical to CHAR_LENGTH and LENGTH for VARCHAR and CHAR inputs. ## Compatibility - Fully conforms to the SQL standard CHARACTER_LENGTH definition. - Interchangeable with CHAR_LENGTH.

Parameters

Name	Type	Description
`str`		Specifies the input string whose character count is returned.

Examples

-- Basic length
SELECT CHARACTER_LENGTH('hello');  -- 5

-- Empty string
SELECT CHARACTER_LENGTH('');  -- 0

-- Multi-byte characters count as one
SELECT CHARACTER_LENGTH('üöä');  -- 3

-- NULL propagates
SELECT CHARACTER_LENGTH(CAST(NULL AS VARCHAR));  -- NULL

-- Trailing spaces are counted
SELECT CHARACTER_LENGTH('abc   ');  -- 6

-- Use in a constraint-style check
SELECT order_id
FROM retail.sales.orders
WHERE CHARACTER_LENGTH(reference_code) <> 10;

Pitfalls

CHARACTER_LENGTH counts code points, not grapheme clusters. Visual width and character count diverge for strings that use combining marks.
It is not a byte count. For storage-size or network-size estimates use OCTET_LENGTH.
Trailing pad spaces in a CHAR(n) value contribute to the length. Wrap in RTRIM if you want the logical length.
Do not confuse with ARRAY length for non-string types. Cast to VARCHAR if the column type is ambiguous.