The freaking alternative LENGTHB function for Oracle unicode environment. if one unicode calculates 3 bytes, this function will give you returning 2 bytes.

fn_lengthk.sql

CREATE OR REPLACE FUNCTION FN_LENGTHK(PS_STR IN VARCHAR2) RETURN NUMBER IS
V_STR_LEN NUMBER;
V_STR_CHR VARCHAR2(3);
V_RES_LEN NUMBER;
/******************************************************************************
   NAME:       FN_LENGTHK
   PURPOSE:    LENGTHB와 동일하나 유니코드 특성상 한글 3바이트로 계산하기 때문
               에 2바이트로 처리하여 출력하기 위한 공통 함수
               유니코드 만세!

   REVISIONS:
   Ver        Date        Author           Description
   ---------  ----------  ---------------  ------------------------------------
   1.0        2017/03/23   Composite       1. Created this function.

   NOTES:

   Automatically available Auto Replace Keywords:
      Object Name:     FN_LENGTHK
      Sysdate:         2017/03/23
      Date and Time:   2017/03/23, 오후 4:23:25, and 2017/03/23 오후 4:23:25
      Username:        Composite
      Table Name:      

******************************************************************************/
BEGIN
    
    V_RES_LEN := 0;
    V_STR_LEN := LENGTH(PS_STR);
    
    IF V_STR_LEN > 0 THEN
    
        FOR i IN 1..V_STR_LEN
        LOOP
            V_STR_CHR := SUBSTR(PS_STR,i,1) ;
            V_RES_LEN := V_RES_LEN + CASE WHEN LENGTHB(V_STR_CHR) > 1 THEN 2 ELSE 1 END;
        END LOOP;
    
    END IF;
    
    RETURN V_RES_LEN;
    
END FN_LENGTHK;



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