plsql / cursors处理异常并返回执行流程

I am trying to execute a cursor and want it to complete the loop even if there is some exception.

我试图执行一个游标,并希望它完成循环,即使有一些异常。

What I trying to do is "catch" all the exception and probaably log somthing or do nothing and then return back to the flow . Here is how the code looks like:

我想要做的是“捕获”所有异常,并且可能记录某些事情或什么也不做,然后返回流程。以下是代码的外观:

 FOR line IN my_cursor
 LOOP
 begin

    if<condition> then
      GOTO pass; 
    else     
     <<do_something>>
     exception
       when others then
        sys.dbms_output.put_line('say something');       
    end if;  

    <<pass>> null;
 end
 END LOOP;

The script doesnt compile. There is probably some syntactic error with the exception , but I am also not aware of semantics very well. Like I am not sure if you can return back to execution flow after handling an exception.

脚本没有编译。异常可能存在一些语法错误,但我也不太了解语义。就像我不确定你是否可以在处理异常后返回执行流程。

p.s: The DB is 10g and there is not CONTINUE in it . Hence using GOTO.

p.s:DB为10g,并且没有CONTINUE。因此使用GOTO。

3 个解决方案

#1

Put the code that you want to execute within the loop in it's own block and then you can use that blocks exception section to handle any problems during the loop iteration.

将您想要在循环中执行的代码放在它自己的块中,然后您可以使用该块异常部分来处理循环迭代期间的任何问题。

Once the exception for that iteration is handled, the next loop iteration will start

一旦处理了该迭代的异常,就会开始下一个循环迭代

e.g.:

for line in my_cursor
loop
   begin    
      <<do_something>>
   exception
      <<do_exception_processing>>        
   end;
end loop;

To illustrate this further, in the example below, I have declared a local variable of type exception. I am looping through numbers 1 to 10, during the second loop iteration, the if statement is true and processing passes to the exception handler. Once the exception is handled, the next iteration of the loop begins.

为了进一步说明这一点,在下面的例子中,我声明了一个异常类型的局部变量。我循环遍历数字1到10,在第二次循环迭代期间,if语句为true,处理传递给异常处理程序。处理完异常后,循环的下一次迭代开始。

begin

   for i in 1 .. 10 
   loop

      declare

         my_exception exception;

      begin

         if i = 2
         then

            -- if you need to do some processing then you would enter it
            -- here and then when you want to enter the exception section 
            -- you would add the line below 

            raise my_exception;

         end if;

      exception
         when my_exception then
            dbms_output.put_line('in exception section');

      end;

   end loop;

end;

#2

FOR line IN my_cursor  
LOOP
  if not some_condition then
    begin
      do_something;
    exception     
      when others then log_my_error(); -- this should be something that uses
                                       -- an autonomous transaction
    end;
  end if;
END LOOP;

#3

 BEGIN 
 FOR Line in My_Cursor LOOP
    IF condition THEN
 BEGIN
    do something...
 END;
    ELSE 
 BEGIN
    do something...
 END;
    END IF;
 END LOOP;
 EXCEPTION
 WHEN OTHERS THEN
 DBMS_OUTPUT.PUT_LINE('say something');
 END;

#1