oracle中sum字符串方法

CREATE OR REPLACE FUNCTION SumString(i_TableName     IN VARCHAR2,
                                     i_GroupColName  IN VARCHAR2,
                                     i_ResultColName IN VARCHAR2,
                                     i_GroupColValue IN VARCHAR2,
                                     i_Separator     IN VARCHAR2)
  RETURN VARCHAR2 IS
  TYPE T_Cur IS REF CURSOR;
  C_Cur    T_Cur;
  V_Sql    VARCHAR2(2000);
  V_Result VARCHAR2(2000);
  V_Tmp    VARCHAR2(200);
  V_Cnt    NUMBER := 0;
BEGIN
  V_Result := ' ';
  V_Sql    := 'SELECT   ' || i_ResultColName || '   FROM   ' || i_TableName ||
              '   WHERE   ' || i_GroupColName || '   =   ' || i_GroupColValue;
  OPEN C_Cur FOR V_Sql;
  LOOP
    FETCH C_Cur
      INTO V_Tmp;
    EXIT WHEN C_Cur%NOTFOUND;
    IF V_Cnt = 0 THEN
      V_Result := V_Tmp;
    ELSE
      V_Result := V_Result || i_Separator || V_Tmp;
    END IF;
    V_Cnt := V_Cnt + 1;
  END LOOP;
  CLOSE C_Cur;

  RETURN V_Result;
END SUMSTRING;