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 CREATE OR REPLACE FUNCTION
       F_Get_day2YYMMDD(In_date CHAR)
       RETURN CHAR IS Out_yymmdd VARCHAR2(50);
      
/* 과거 시점부터 현재일까지의 일수를 년월일로 반환*/
      
Begin
  SELECT  TRUNC (mb / 12) || '년'
       ||TRUNC (MONTHS_BETWEEN (SYSDATE
                               , ADD_MONTHS ( to_date(In_date,'yyyymmdd'), 12 * TRUNC (mb / 12))
                                )
                )
       || '개월'
       ||TRUNC (SYSDATE - ADD_MONTHS ( to_date(In_date,'yyyymmdd'), TRUNC (mb))) || '일' yymmdd
  into Out_yymmdd
    
  FROM (SELECT MONTHS_BETWEEN (SYSDATE, to_date(In_date,'yyyymmdd')) mb FROM dual);
 
 
   Return (Out_yymmdd);
  
  
Exception
     WHEN NO_DATA_FOUND THEN
      RETURN null;
End F_Get_day2YYMMDD;

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