Out of curiousity, why would you add a flag?

--- In firebird-support@yahoogroups.com, "Adam" <s3057043@y...> wrote:
> >
> > My question is (a) does this sound like a good solution for speeding
> > up my inserts and (b) are there hidden gotchas in this solution that I
> > am not considering?
> >
> > This table doesn't really have indices besides it's primary key so
> > that approach really wont impact performance, and even if it did I
> > don't think the insert performance change would be as drammatic as
> > this solution.
> >
>
> Hi Robert,
>
> I would add a flag to your table to specify which field the data is
> stored in, rather than testing for NULL.
>
> Also (based on your second posting), why have you declared your field
> to be 2000 characters if you only ever store 1000 characters in it?
> You will obviously need to do some tests on your data shape (eg. Max
> field length required to date, average field length to date, and some
> sort of graph of these). You can then do some experiments to see the
> impact of different field sizes on the total database size and the
> insert performance.
>
> You may want to also consider changing the table structure a bit so
> that perhaps you use a second table.
>
> Table2
> (
> ID integer,
> Sequence integer,
> MyData varchar(whatever size is "optimum")
> )
>
> Then each record in your main table could store a table2ID, join to
> table2 and run an order by on the sequence. The server could query all
> records in Table2 and rebuild its data array. This could be done quite
> efficiently, whether it will be faster or slower is not an academic
> discussion, you will need to test it to see if it is worthwhile.
>
> Secondly, consider on the fly compression if you haven't already. You
> should be able to find some low resource requirement compressor that
> achieves significant reduction in size.
>
> Hope that is some ideas
>
> Adam.