Posted by Erland Sommarskog on 10/19/05 01:06

(wackyphill@yahoo.com) writes:
> If you have several entities that have many common properties but a few
> have a few unique fields to them how do you design your tables?
>
> DO you make a seperate table for each entity even though they have many
> common fields or is there a way to do an OO type thing where you have a
> common table for all and somehow tack on the unique fields?
>
> Just unsure whats possible and what's best.

Basically as Steve says.

One has to be a little careful, and not overdo it. If it's only one or
two extra columns, maybe it's better to keep them in the main table.
Or let several "subclasses" share a table.



--
Erland Sommarskog, SQL Server MVP, esquel@sommarskog.se

Books Online for SQL Server SP3 at
http://www.microsoft.com/sql/techinfo/productdoc/2000/books.asp

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