Re: data structure complexity vs. application maintenance cost

On Feb 23, 1:31 pm, "H. S. Lahman" <h.lah...@xxxxxxxxxxx> wrote:

So one typically isolates the persistence access in a subsystem that is
constructed after the rest of the problem is solved. The interface to
that subsystem is based on the problem solution's needs for data and the
subsystem exists to convert between the solution view and the
persistence view. Then, given that the views are decoupled, it becomes
relatively easy to design the persistence view (e.g., RDB schema) that
works best.

I have to concur with Topmind's and JXStern's comments. It's bad
advise, in general, to build up a complete representation of data in
the application's space, with code, along the lines suggested here.
The RDBMS is a tool for managing data access. It goes far beyond
persistence, it's scalable and fault tolerant in the way that many
home grown approaches are not, and provides a logic based querying
capability that is richer than the typical home grown code based
filter. Managing large amounts of state in the application is not
usually a good idea, there are tools for that. Generally speaking,
the idea in software assembly these days is to leverage tools, where
appropriate.

Best regards,
Daniel


.

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