Re: Need Help for select

On Wed, 14 Aug 2002 21:57:02 +0900
"Masaru Sugawara" <rk73(at)sea(dot)plala(dot)or(dot)jp> wrote:

> On Wed, 14 Aug 2002 09:10:53 +0200
> Andre Schubert <andre(at)km3(dot)de> wrote:
>
> > The ride side as follows.
> > Table d contains information about subitems.
> > Table c holds information about subitems and items of type bar.
> > Each subitem can have 0..n items bar selected.
> >
> > What i want is that a subitem is only activated for a foo item if
> > the foo-item has exactly selected the same bar items selected as
> > as the relation between table c and d.
> >
> > Example 1:
> > The foo-item A_Name1 has selected the bar-items 1 and 2.
> > The subitem D_Name1 is only activated for a foo-item if that foo-item
> > has selected the bar-items 1 and 2, this happens for A_Name1.
> >
>
>
> If this mention implies that the tuple of (1, 1) in the c is supposed
> to take precedence over that of (2, 1),

I want to compare if a tuple in c exist in b for each c.d_id and b.a_id.
In c exists 3 tuples: (1,2), (3,4), (5)
and want to find these tuples in b.

select a.name,d.name from a,b,c,d where "tuple found in b" = "tuple found in c" and b.a_id = a.id and c.d_id = d.id

My english is not so good, but i hope you understand what i want to do.

Thanks in advance

>
>
> SELECT a.name, d.name
> FROM (SELECT DISTINCT min(b.a_id) AS a_id, c.d_id
> FROM b, c
> WHERE b.c_id = c.b_id
> GROUP BY b.c_id, c.d_id
> ) AS t,
> a,
> d
> WHERE a.id = t.a_id
> AND d.id = t.d_id
>
>
>
> Regards,
> Masaru Sugawara
>
>
>
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