Re: Speed of data retrival
From: Niall Litchfield <niall.litchfield_at_dial.pipex.com>
Date: Thu, 30 May 2002 11:59:47 +0100
Message-ID: <3cf60626$0$8509$cc9e4d1f_at_news.dial.pipex.com>
Date: Thu, 30 May 2002 11:59:47 +0100
Message-ID: <3cf60626$0$8509$cc9e4d1f_at_news.dial.pipex.com>
that'll teach me to be smart.
-- Niall Litchfield Oracle DBA Audit Commission UK "Daniel Morgan" <dmorgan_at_exesolutions.com> wrote in message news:3CF5615B.44B816B1_at_exesolutions.com...Received on Thu May 30 2002 - 12:59:47 CEST
> Niall Litchfield wrote:
>
> > "Daniel Morgan" <dmorgan_at_exesolutions.com> wrote in message
> > news:3CF3A073.9957EFE2_at_exesolutions.com...
> > > Stjepan Brbot wrote:
> > >
> > > > What is the difference according to speed of data retrival or any
other
> > > > aspect of execution speed if one uses more columns in SELECT
> > > > SQL-statement?
> > > >
> > > > Is there any difference in retrival of these two SELECT statements:
> > > >
> > > > SELECT col1,col2,col3 FROM table1 WHERE col1=4
> > > >
> > > > and
> > > >
> > > > SELECT col1,col2 FROM table1 WHERE col1=4
> > > >
> > > > --
> > > >
> > > > Stjepan Brbot
> > >
> > > Immeasureably small.
> >
> > In general but it depends on the data
> >
> > select title,date from films where director = 'HITCHCOCK';
> >
> > will be considerably faster than
> >
> > select title,date,video_content from films where director = 'HITCHCOCK';
> >
> > --
> > Niall Litchfield
> > Oracle DBA
> > Audit Commission UK
>
> If by content you mean "BLOB" I whole-heartedly agree.
>
> On the other hand ... SELECT blob_field FROM table is a real non-starter.
>
> Daniel Morgan
>