Syntax

length::=

Purpose

The LENGTH functions return the length of char. LENGTH calculates length using characters as defined by the input character set. LENGTHB uses bytes instead of characters. LENGTHC uses Unicode complete characters. LENGTH2 uses UCS2 code points. LENGTH4 uses UCS4 code points.

char can be any of the data types CHAR, VARCHAR2, NCHAR, NVARCHAR2, CLOB, or NCLOB. The exceptions are LENGTHC, LENGTH2, and LENGTH4, which do not allow char to be a CLOB or NCLOB. The return value is of data type NUMBER. If char has data type CHAR, then the length includes all trailing blanks. If char is null, then this function returns null.

For more on character length see the following:

• Oracle Database Globalization Support Guide

• Oracle Database SecureFiles and Large Objects Developer's Guide

Restriction on LENGTHB

The LENGTHB function is supported for single-byte LOBs only. It cannot be used with CLOB and NCLOB data in a multibyte character set.

Examples

The following example uses the LENGTH function using a single-byte database character set:

SELECT LENGTH('CANDIDE') "Length in characters"
  FROM DUAL;

Length in characters
--------------------
                   7

The next example assumes a double-byte database character set.

SELECT LENGTHB ('CANDIDE') "Length in bytes"
  FROM DUAL;
 
Length in bytes
---------------
             14