ORA-06502 错误
DECLARE
    RESULT   VARCHAR2(255);
    CURSOR   cur_eq   IS
        SELECT   column_name
            FROM   user_tab_columns
          WHERE   table_name   =   'EQUIPMENT ';
    v_col   user_tab_columns.column_name%TYPE;
BEGIN
    OPEN   cur_eq;
    LOOP
        FETCH   cur_eq
            INTO   v_col;
        RESULT   :=   RESULT   ||   v_col   ||   ', ';   --   这句编译出错
        EXIT   WHEN   cur_eq%NOTFOUND;
    END   LOOP;
    CLOSE   cur_eq;
    dbms_output.put_line(RESULT);
END;

------解决方案--------------------
SQL> DECLARE
2 RESULT VARCHAR2(255);
3 CURSOR cur_eq IS
4 SELECT column_name
5 FROM user_tab_columns
6 WHERE table_name = 'T_SITE ';
7 v_col user_tab_columns.column_name%TYPE;
8 BEGIN
9 OPEN cur_eq;
10 LOOP
11 FETCH cur_eq
12 INTO v_col;
13 RESULT := RESULT || v_col || ', '; -- 这句编译出错
14 EXIT WHEN cur_eq%NOTFOUND;
15 END LOOP;
16 CLOSE cur_eq;
17 dbms_output.put_line(RESULT);
18 END;
19 /

UUID,SITETYPEID,NAME,CODE,TYPE,ADDRESS,PROPERTYRIGHTTYPE,XPOSITION,YPOSITION,SUBREGIONID,DMDZID,DMDZID,

PL/SQL procedure successfully completed

不是编译的错，估计是RESULT VARCHAR2(255);太小，超出长度了
------解决方案--------------------
改成RESULT VARCHAR2(4000);