John,
Although I generally agree, there are times when creating the temporary
table, or creating a table to store aggregate data is appropriate.
I worked on an application not to long ago that had a number of reports that
were each based on the same aggregate query (actually this was a series of
queries). This query took several minutes to run, but since the users were
only concerned with the information as of the close of the previous business
day, I was able to significantly improve the time it took the users to
generate these reports by populating an aggregate table first thing each
morning.
--
Dale
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"John W. Vinson" wrote:
> On Mon, 2 Feb 2009 08:07:02 -0800, David <(E-Mail Removed)>
> wrote:
>
> >When creating a table from a make table query- always get the sumof as part
> >of the new column heading- other than by changing the name of the column in
> >the first query- can I stop access changing the column name? i.e leave out
> >the "sumof" but still do the calculation?
>
> I'd question whether *either* a MakeTable query OR storing calculated data is
> appropriate in any case!
>
> Storing derived data such as this in your table accomplishes
> three things: it wastes disk space; it wastes time (almost
> any calculation will be MUCH faster than a disk fetch); and
> most importantly, it risks data corruption. If one of the
> underlying fields is subsequently edited, you will have data
> in your table WHICH IS WRONG, and no automatic way to detect
> that fact.
>
> Just redo the calculation whenever you need it as a
> calculated field in a Query; you can base reports, forms, etc. on that query.
> --
>
> John W. Vinson [MVP]
>
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