oracle 声明用户定义的异常

Question

Oracle SP 没有编译

我在 MS SQL 方面很有经验，但在上 Oracle 类(class)时，我无法弄清楚为什么这个存储过程脚本不起作用。我在第一个异常变量的变量声明部分遇到错误。这是错误消息:

 PLS-00103: Encountered the symbol "EXCEPTION" when expecting one of the following:
 in out <an identifier> <a double-quoted delimited-identifier> LONG_ double ref char
 time timestamp interval date binary national character nchar

代码

CREATE or REPLACE Procedure Movie_Rental_SP
(
Mv_ID IN Number,
Mem_ID IN Number,
Pay_ID IN Number,
Mv_Chk Number,
Mem_Chk Number,
Pay_Chk Number,
Qty_Chk Number,
--> next line is where the error points
      UnKnown_Mv Exception,
UnKnown_Mem Exception,
UnKnown_Pay Exception,
UnAvail_Mv Exception    )

IS

BEGIN
SELECT COUNT(Movie_ID) INTO Mv_Chk FROM MM_Movie WHERE Movie_ID = Mv_ID; 
SELECT COUNT(Member_ID) INTO Mem_Chk FROM MM_Member WHERE Member_ID = Mem_ID;
SELECT COUNT(Payment_Methods_ID) INTO Pay_Chk FROM MM_Pay_Type WHERE Payment_Methods_ID = Pay_ID;
SELECT Movie_Qty INTO Qty_Chk FROM MM_Movie WHERE Movie_ID = Mv_ID;

IF       Mv_Chk = 0 THEN RAISE UnKnown_Mv;
ELSE IF Mem_Chk = 0 THEN RAISE UnKnown_Mem;
ELSE IF Pay_Chk = 0 THEN RAISE UnKnown_Pay;
ELSE    Qty_Chk = 0 THEN RAISE UnAvail_Mv;
END IF; 

    DECLARE New_ID NUMBER;
    BEGIN
        SELECT Max(Rental_ID)+1 INTO New_ID FROM MM_Rental;
        EXCEPTION WHEN NO_DATA_FOUND THEN
            New_ID := 1;
            DBMS_OUTPUT.PUT_LINE ('There are no exsisting Rental IDs, ID set to 1');
    END;

INSERT INTO MM_Rental VALUES (New_ID,Mem_ID,Mv_ID,Sysdate,Null,Pay_ID);
UPDATE MM_Movie SET Movie_Qty = Movie_Qty - 1 WHERE Movie_ID = Mv_ID;

EXCEPTION 
    WHEN UnKnown_Mv THEN 
        RAISE_APPLICATION_ERROR(-20001,'There is no movie with Movie ID of: '||Mv_ID||' Transaction cancelled.');
    WHEN UnKnown_Mem THEN 
        RAISE_APPLICATION_ERROR(-20002,'No member exists with member ID: '||Mem_ID||' Transaction cancelled.');
    WHEN UnKnown_Pay THEN
        RAISE_APPLICATION_ERROR(-20003,'No payment type for: '||Pay_ID||' Transaction cancelled.');
    WHEN UnAvail_Mv THEN
        RAISE_APPLICATION_ERROR(-20004,'No movies available for: '||Mv_ID||' Transaction cancelled.');
    WHEN OTHERS THEN
        DBMS_OUTPUT.PUT_LINE ('Error number: '||sqlcode);
        DBMS_OUTPUT.PUT_LINE ('Error message: '||sqlerrm);
        DBMS_OUTPUT.PUT_LINE('Unanticipated error.  Contact your system administrator.');
END;
/

任何帮助将不胜感激!

Answer 1

我的假设是，在三个 IN 参数之后，您的意图是将其他所有内容声明为局部变量，而不是过程的参数。将异常传递给过程是没有意义的。您的“ELSE IF也需要是ELSIF”。

CREATE or REPLACE Procedure Movie_Rental_SP
(
  Mv_ID IN Number,
  Mem_ID IN Number,
  Pay_ID IN Number
)
AS
  Mv_Chk Number;
  Mem_Chk Number;
  Pay_Chk Number;
  Qty_Chk Number;
  UnKnown_Mv Exception;
  UnKnown_Mem Exception;
  UnKnown_Pay Exception;
  UnAvail_Mv Exception;  
BEGIN
  SELECT COUNT(Movie_ID) INTO Mv_Chk FROM MM_Movie WHERE Movie_ID = Mv_ID; 
  SELECT COUNT(Member_ID) INTO Mem_Chk FROM MM_Member WHERE Member_ID = Mem_ID;
  SELECT COUNT(Payment_Methods_ID) INTO Pay_Chk FROM MM_Pay_Type WHERE Payment_Methods_ID = Pay_ID;
  SELECT Movie_Qty INTO Qty_Chk FROM MM_Movie WHERE Movie_ID = Mv_ID;

  IF    Mv_Chk = 0 THEN RAISE UnKnown_Mv;
  ELSIF Mem_Chk = 0 THEN RAISE UnKnown_Mem;
  ELSIF Pay_Chk = 0 THEN RAISE UnKnown_Pay;
  ELSE  Qty_Chk = 0 THEN RAISE UnAvail_Mv;
  END IF; 

  DECLARE 
    New_ID NUMBER;
  BEGIN
    SELECT Max(Rental_ID)+1 INTO New_ID FROM MM_Rental;
  EXCEPTION WHEN NO_DATA_FOUND THEN
     New_ID := 1;
     DBMS_OUTPUT.PUT_LINE ('There are no exsisting Rental IDs, ID set to 1');
  END;

  INSERT INTO MM_Rental VALUES (New_ID,Mem_ID,Mv_ID,Sysdate,Null,Pay_ID);
  UPDATE MM_Movie SET Movie_Qty = Movie_Qty - 1 WHERE Movie_ID = Mv_ID;
EXCEPTION 
  WHEN UnKnown_Mv THEN 
     RAISE_APPLICATION_ERROR(-20001,'There is no movie with Movie ID of: '||Mv_ID||' Transaction cancelled.');
  WHEN UnKnown_Mem THEN 
      RAISE_APPLICATION_ERROR(-20002,'No member exists with member ID: '||Mem_ID||' Transaction cancelled.');
  WHEN UnKnown_Pay THEN
      RAISE_APPLICATION_ERROR(-20003,'No payment type for: '||Pay_ID||' Transaction cancelled.');
  WHEN UnAvail_Mv THEN
      RAISE_APPLICATION_ERROR(-20004,'No movies available for: '||Mv_ID||' Transaction cancelled.');
  WHEN OTHERS THEN
      DBMS_OUTPUT.PUT_LINE ('Error number: '||sqlcode);
      DBMS_OUTPUT.PUT_LINE ('Error message: '||sqlerrm);
      DBMS_OUTPUT.PUT_LINE('Unanticipated error.  Contact your system administrator.');
END;
/

作为一般原则，不重新引发异常的WHEN OTHERS 异常处理程序几乎肯定是一个错误。将数据写入 dbms_output 并不能以任何方式保证任何人都能看到数据或在任何地方持久保存数据。所以，例如

  WHEN OTHERS THEN
      DBMS_OUTPUT.PUT_LINE ('Error number: '||sqlcode);
      DBMS_OUTPUT.PUT_LINE ('Error message: '||sqlerrm);
      DBMS_OUTPUT.PUT_LINE('Unanticipated error.  Contact your system administrator.');
      RAISE;

将重新抛出之前引发的任何异常。当然，如果您只是没有捕捉到您无法处理的异常，您也会得到相同的行为。