Re: Are redundant fields ever appropriate?

71062.1056_at_compuserve.com (--CELKO--) wrote:

> >> Apologies for using SQL-Server extensions in the form of IDENTITY
> fields - this reduces the keys to a manageable size. What equivalent
> support is there in other DMBSs (Oracle?) or in the SQL standard for
> this sort of thing (apart from allocating unique IDs manually)? <<
 

> Real SQL has nothing like the IDENTITY column. It is not only
> proprietary, it is non-relational, not verifiable aganst the reality
> being modeled, and usually the result of a lazy database designer who
> did not want to deal with thinking about how to model his situation.
> I have a really long rant about the evils of IDENTITY I might post
> later.

Please do - I can't see why there's a problem with the identity column - it provides an easy way of defining a primary key for any/all tables.

I have also seen people whose opinion I respect (who provide help on the Borland newsgroups) recommending them (BTW, this doesn't mean that I don't respect your opinion (I'm planning to run out and buy 1 or 2 of your texts in the near future 8-) )

Using identity columns (or in InterBase, generators or in other systems autoinc fields) also simplifies SQL statements greatly.  

> There are some other matter in your DDL, besides the proprietary NULL
> constraints, etc. Tables are sets of things, so their names should be
> plural.

Do you think that one can ever be justified in having a table with just one row?

Paul...

--
Paul Linehan

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