Question

我正在尝试触发更新Video表。我得到了这一点，通过谷歌和其他任何东西，但似乎无法找到所有这些错误的答案任何帮助或建议将不胜感激。这是错误的触发器。

CREATE or REPLACE Trigger Available_Rule

 BEFORE INSERT ON Transaction
 FOR EACH ROW

BEGIN
SELECT (*) 
FROM Video, Transaction
WHERE Status = :new.Status;

IF :new.Date_Rented_Out  is not null AND IF :new.Date_Returned = NULL
 THEN 
   UPDATE Video
   set Status = Unavailable
   where Status = :new.Status;
 End IF;
 END;
/
show errors;

2/1  PL/SQL: SQL Statement ignored  
2/9  PL/SQL: ORA-00936: missing expression  
4/16  PLS-00049: bad bind variable 'NEW.STATUS'  
6/42  PLS-00103: Encountered the symbol "IF" when expecting one of the following: ( - + case mod new not null <an identifier> <a double-quoted delimited-identifier> <a bind variable> avg coun t current exists max min prior sql stddev sum variance execute forall merge time timestamp interval date <a string literal w ith character set specification> <a number> <a single-quoted S QL string> pipe <an alternatively-quoted string literal with c haracter set specification> <an alternatively-quoted  
10/19  PLS-00049: bad bind variable 'NEW.STATUS'  
12/5  PLS-00103: Encountered the symbol "end-of-file" when expecting on e of the following: end not pragma final instantiable order o verriding static member constructor map

Answer 1

改变这个：

IF :new.Date_Rented_Out  is not null AND IF :new.Date_Returned = NULL

到此：

IF :new.Date_Rented_Out  is not null AND :new.Date_Returned is NULL

失去= NULL和额外的IF

这些触发错误意味着什么

1 个答案: