Re: The..Horror.....The..Horror.

This kind of thing happens because we create "test" databases and don't usually include many constraints that will make our "testing" more complex than it needs to be and besides, creating all those constraints will take time -- and for right now we just need to load the data to test the application.

Many of these "test" databases, when we're faced with surprise deadlines and changes in schedules go directly into production -- without the data constraints that are required by the business. As time goes by, people assume there was some valid, techincal reason for not having included the data constraints and that the integrity of the data will somehow see to itself.

Always include all data integrity constraints, including RI, as early as possible.

Pat Minnis wrote:

> True that referential integrity is best. But you could cause problems for
> the application by adding it. (You probably already realized that
> already -- the horror.) I would just come up with scripts to show child
> records without a parent and hand them over to the developers -- daily.
> :-)
>
> Joe & Anne Buhl wrote in message <369AC877.568BEC27_at_worldnet.att.net>...
> >Hello,
> >
> >I just took a new position at a small company. I was not to disturbed
> >to find out that they do not utilize referential integrity constraints.
> >But to my horror, I found out today that they actually create child
> >records with which there is no parent. Sequence numbers are used
> >exclusively. They create the foriegn key as a sequence number then when
> >they need attributes from the parent they create the parent record.
> >
> >This violates one of Codds original principals of the relational model.
> >I don't have any experience with this type of activity. I don't know
> >what kind of problems it causes other than having a bunch of orphan
> >records in the table. It seems to me that it is no longer a relational
> >database but a database dump.
> >
> >Can any of you give me some real world examples of the problems this can
> >cause.
> >
> >Please copy me at jbuhl_at_commerce.com for your responses.
> >
> >Thanks
> >
> >joe
> >

--
Ric Sullivan, Database Administrator
Harvard University, Financial Administration Information Resources & Services

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