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Re: Need help with a SQL query

From: Joseph Wilson <me_at_home.now>
Date: Thu, 27 Mar 2003 03:07:03 GMT
Message-ID: <rVtga.2760$2x2.1158630@dca1-nnrp1.news.algx.net>


Yes, you are correct. A simple union will perform the extra step of removing duplicates. When your query will obviously not have duplicates the union all is a more efficient choice.

Joe

"Anurag Varma" <avdbi_at_hotmail.com> wrote in message news:3Fsga.1837$ec3.1296_at_news01.roc.ny.frontiernet.net...
> Not wanting to nitpick .. and it does not matter much in this case.
> But imho using "union all" is better when you don't really need union.
>
> Anurag
>
> "Joseph Wilson" <me_at_home.now> wrote in message
news:qWrga.2735$2x2.1154317_at_dca1-nnrp1.news.algx.net...
> > select 'a' as ATTRIBUT , count(*) as no from table1 where a is not null
> > UNION
> > select 'b' as ATTRIBUT, count(*) as no from table1 where b is not null
> > UNION
> > select 'c' as ATTRIBUT, count(*) as no from table1 where c is not null
> >
> >
> > "Anders Windelhed" <anders_at_underlandstudios.com> wrote in message
> > news:txqga.30193$oe.93724_at_amstwist00...
> > > I need help with a SQL query...
> > >
> > > I have three queries:
> > >
> > > (select 'a' as ATTRIBUT , count(*) as no from table1 where a is not
null)
> > >
> > > (select 'b' as ATTRIBUT, count(*) as no from table1 where b is not
null)
> > >
> > > (select 'c' as ATTRIBUT, count(*) as no from table1 where c is not
null)
> > >
> > > the results from these queries looks like this
> > >
> > > attribut no
> > > a 34
> > >
> > > and so on...
> > >
> > > I would like to combine into one result table like this
> > >
> > > attribut no
> > > a 34
> > > b 334
> > > c 23
> > >
> > > I know that it would be much easier to create a query that gives the
> > result
> > > like this
> > >
> > > a b c
> > > 34 334 23
> > >
> > > but that won't solve my problem =(
> > >
> > > Any suggestions?
> > >
> > > Best regards
> > >
> > > Anders
> > >
> > >
> >
> >
>
>
Received on Wed Mar 26 2003 - 21:07:03 CST

Original text of this message

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