Re: Database Redesign and Migration

kramer31 wrote:
> Hi. I apologize if this post is off topic but it doesn't relate to any
> particular database, so I'm posting here.
>
> I've come to work for a new (very small) company as an application
> developer. The legacy code that is here is rather poorly written and
> the database which provides the infrastructure is rather poorly
> designed.
>
> Now the database is not really that complicated, so I think that can
> redesign it in a better way (new tables to store data rather than limit
> numbers of fields where there should not be limits, better naming
> conventions, etc.).
>
> The problem is that redesigning will require a code re-write and will
> require our users to update and for us to do something to migrate their
> data. We are sort of looking at two options:
>
> 1) We can redesign the database all at once and slog through the
> re-write and migration or
> 2) We can redesign it a table or two at a time
>
> It seems that 1) should allow us more flexibility in design. I've read
> a couple of texts that strongly suggest redesigning from scratch rather
> than making changes to the old database structure, but 2) should make
> the code rewrite easier.
>
> I'm also not very familiar with data migration. Can anyone recommend a
> reference on that?
>
> Thanks.
>

My two cents is that before you decide to re-design/re-write part or all of it, you need to quantify in terms the biz mgmt digs, just what the 'poorly written' and 'poorly-designed' aspects are costing the 'very small company' (unless it can be shown that some crucial enhancement is impossible without re-implementing the old part). For example, does the 'limited numbers of fields' tie the business' hands in some way that trumps any dollars and sense estimate? If, on the other hand, the 'problem' has to do with code niceties or your initial unfamiliarity with why this or that was done this or that way, I suggest you are jumping the gun and it would be better to learn the appl'n inside and out before researching outside texts.

p

p Received on Wed Nov 22 2006 - 00:52:45 CET