Re: what is the SQL equivalent of 'continue' and 'break' in C ?

From: Rauf Sarwar <rs_arwar_at_hotmail.com>
Date: 10 Aug 2006 06:44:44 -0700
Message-ID: <1155217484.370023.195710@m79g2000cwm.googlegroups.com>

happyardy_at_gmail.com wrote:
> DA Morgan wrote:
> > happyardy_at_gmail.com wrote:
> > > Scott wrote:
> > >> happyardy_at_gmail.com wrote:
> > >>> what is the SQL equivalent of 'continue' and 'break' in C ?
> > >>>
> > >>> like can I do this...
> > >>>
> > >>>
> > >>> for counter in 1..10
> > >>> if(something something)
> > >>> ( if (something)
> > >>> ( if(something)
> > >>> then continue;
> > >>>
> > >>> //Rest of the for loop
> > >>>
> > >>> end loop;
> > >>>
> > >>> Would it start the next iteration without processing the rest of the
> > >>> loop ?
> > >>>
> > >>> thanks
> > >>> - Ardy
> > >> If I understand the question, something like this in PL/SQL
> > >>
> > >> loop
> > >>
> > >> loop
> > >> if something
> > >> then
> > >> exit; -- continue, i.e. go on with the rest of the main loop
> > >> end if;
> > >>
> > >> end loop;
> > >>
> > >> if something_else
> > >> then
> > >> exit; -- break, i.e. get out of the main loop
> > >> end if;
> > >> -- rest of the for loop
> > >>
> > >> end loop;
> > >
> > > Scott,
> > > I am a little confused about if this works the way, 'continue' works in
> > > C language. I mean in the middle of a for loop if I have a "continue;"
> > > in C language, the control just goes to the top of the loop and starts
> > > a new iteration.
> > > In your code here, 'exit'' would break me out of the inner loop and the
> > > control would go to first statement(if any) that is outside the inner
> > > loop. I have a bunch of statements in my code after the inner loop.
> > > What I want to happen is that the control goes directly to the next
> > > iteration without trying to execute any of the remaining code outside
> > > of the inner loop..
> > > Your code would hold good if it is the last piece of code in my outer
> > > loop(for loop). That means it would be good if as soon as my inner loop
> > > ends, my outer loop ends too.
> > >
> > > Not saying that your code is wrong but your code will go down and
> > > execute my remaining statements after the inner loop though I dont want
> > > it to. If I wanted to do that then I wouldnt want a 'continue' like
> > > working, now would I ?
> > >
> > > Please let me know if I am not understanding correctly and have
> > > misinterpreted anything.
> > > thanks & regards
> > > - Rahul
> >
> > If you want GOTO capability in Oracle use a label.
> >
> > http://download-west.oracle.com/docs/cd/B19306_01/appdev.102/b14261/goto_statement.htm#LNPLS01323
> >
> > I don't have any demos in the library that I can recall as I
> > find them rather inelegant.
> > --
> > Daniel A. Morgan
> > University of Washington
> > damorgan_at_x.washington.edu
> > (replace x with u to respond)
> > Puget Sound Oracle Users Group
> > www.psoug.org

>

> Daniel,
> I try to stay away from GOTO. GOTOs are not evils and are helpful
> sometimes but still I dont like to use them. I avoid them as much as
> possible.
> I was trying to find out if SQL has any keyword that is equivalent of
> 'continue' in C. C has GOTO too and I have always wanted to avoid that.
> thanks
> - Ardy

GOTO may not be very popular but in your situation... this may be the only option in plsql that you can use. Alternately, you can make use of a boolean flag like,

declare

   bok_ boolean;
begin

   for ... loop

      bok_ := true;
      for ... loop
         if (something) then
            bok_ := false;
            exit; -- This will exit the inner loop with bok_ = false
         end if;
      end loop;
      if (bok_) then
         -- rest of the code
      end if;

   end loop;
end;
/ Received on Thu Aug 10 2006 - 08:44:44 CDT