Re: preventing 2 rows with same "flag" set

Eric Givler wrote:
>
> Ok...
>
> I opened the form, put the code in the when-checkbox-changed, and then ran
> it. I queried on a user
> with 2 locations. I set the checkbox on each row and then committed and now
> have two flags. Forms
> doesn't post the data between record movements on a single block form, so it
> doesn't SEE the other flag
> as set in the database when the trigger fires.
>
> I also want to allow this for updates too. If there's a primary, I should
> be able to uncheck it, then re-check
> another one.
>
> I wasn't sure why the code you posted didn't check to see that the user has
> actually SET THE
> FLAG. It just checks for a flag already set.
>
> Any additional input greatly appreciated, and thanks for the help so far.
>
> Matt B. <mcb_at_fightspam.sd.znet.com> wrote in message
> news:su7nbjfl1a6df_at_corp.supernews.com...
> > "Eric Givler" <egivler_at_flash.net> wrote in message
> > news:tNHE5.757$ln6.112709_at_news.flash.net...
> > > I have a one block form that has a "flag" that stands for "primary
> > > location". The user can have many locations that they are allowed
 access
> > > to, but only ONE primary. If the flag is set (the DB has a "Y" in it),
 then
> > > it is brought up as the default location when they enter the
 application,
> > > otherwise they have to select from a list.
> > >
> > > I've created a checkbox for the field, but how do I prevent/allow the
 user
> > > to only have ONE "flag" for all his locations instead of multiple? What
> > > triggers/code are necessary? I'm using Developer 1.3.2 (32-bit).
> > >
> > > Any ideas appreciated.
> >
> > On WHEN-CHECKBOX-CHANGED:
> >
> > v_flag_found BOOLEAN := FALSE;
> > v_dummy CHAR(1) := NULL;
> > cursor flag_checker is
> > select 'X' from my_table
> > where my_column = 'Y';
> >
> > begin
> > open flag_checker;
> > fetch flag_checker into v_dummy;
> > if flag_checker%FOUND THEN
> > v_flag_found := TRUE;
> > end if;
> > close flag_checker;
> >
> > if v_flag_found THEN
> > message('You cannot do this.');
> > raise form_trigger_failure;
> > end if;
> >
> > -Matt
> >
> >

[Quoted] [Quoted] Can't you set the item to be 'unique' (and have a unique key underneath it) with the only valid values being Y and null

HTH

-- 
===========================================
Connor McDonald
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