Re: relational and hierarchical database

"Prashanth Cannanbilla" <pcannanbilla_at_federatedinv.com> wrote in message news:661b2f41.0111271024.69258c14_at_posting.google.com...

> barthelmes_s_at_ibb.de (S. Barthelmes) wrote in message news:<f8ddfc25.0111270104.2b1b2a60_at_posting.google.com>...
> > Can anyone please explan me the main differences between a relational
> > and a hierarchical database?

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>
> Relational Database model:
>

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One additional concept to organize things in your mind that I picked-up in one of my references relating to the relational model:

"The relationship does not exist until such time that a query is performed".

Basically, there are a lot of indpendent elements of data twirling around. The database engine permits you to define and determine a relationship (by query) and delivers the results.

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