String Length Functions (SQL)

CHAR_LENGTH(arg)  
OCTET_LENGTH(arg)  
BIT_LENGTH(arg)

The functions CHAR_LENGTH, OCTET_LENGTH and BIT_LENGTH return the argument length. The argument must either be a string or binary type (CHAR, NCHAR, CLOB, NCLOB, BLOB, BIT, BINARY). The first function returns the character count, the second returns the length in bytes, and the third returns the length in bits.

The following table shows the results of these functions for the same string. First as CHAR type and then as NCHAR type (2-byte Unicode):

string '602sql'	as CHAR	as NCHAR
CHAR_LENGTH	6	6
OCTET_LENGTH	6	12
BIT_LENGTH	48	96

SQL properties defined by implementation in 602SQL

These functions return the full argument length when used for a BINARY type variable, regardless of the value. For the BOOLEAN (BIT) type, the return value is always 1. For character string types, the return value is the actual length of the string. For variable-length types, the return value is the actual value length.

602SQL Variations

602SQL does not distinguish between a blank value and NULL value for string and text types. The meaning of these two values are equivalent. If the argument is a string or text with the NULL value, the result is always 0.

Example:

Function that returns the length (character count) of a parameter.

FUNCTION DELKACHAR (strpar CHAR (100)) RETURNS INT;
BEGIN
  RETURN (CHAR_LENGTH(strpar));
END

See

POSITION Function

Functions Defined by the SQL Standard

SUBSTRING Function