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Posted by Tony Rogerson on 11/06/05 18:51
In your book 'sql for smarties' you have an example with a table named
'Warehouse' - if you where to follow your own naming standards then it
should be called 'Warehouses'.
'id' is fine within the context of the table, if the column belongs to the
table 'Child' then its obviously Child.id.
What key would you use for a message board? Would you still key it on
subject and posting date or like the rest of us and how NNTP works, create a
guid with the domain?
The auto-number (IDENTITY property) is usually used as a artificial (or
surrogate) key, there is no such thing as a relational key - I think you
mean 'natural key', see: http://en.wikipedia.org/wiki/Natural_key.
Quoting from that aritcle...
"
The main disadvantage of choosing a natural key is that it may need to
change if your business requirements change. For example, if you have chosen
CustomerNumber as the primary key for a customer, and, subsequently,
CustomerNumber becomes alphanumeric instead of numeric, then as well as
changing the type of the column, you will need to make changes to all other
tables where CustomerNumber is used as a foreign key.
Retrieved from "http://en.wikipedia.org/wiki/Natural_key"
"
--
Tony Rogerson
SQL Server MVP
http://sqlserverfaq.com - free video tutorials
"--CELKO--" <jcelko212@earthlink.net> wrote in message
news:1131243682.809956.301200@g49g2000cwa.googlegroups.com...
>>> this is my first database, so I'm just in the learning process really.
>>> <<
>
> Get a book on RDBMS and learn why an auto-increment can NEVER be a
> relational key. Learn why a table name should be a collective or
> plural name (unless there is only one row in the table). Learn way
> "id" is too vague to be data element name. Learn why camelCase is a
> bitch to read --hint: where does your eye jump when you see an
> Uppercase letter?
>
> I know you want to have a "Magical Universal Key" that will solve all
> your design problems, without having to really think or learn anything.
> What is your **real key** in your **real** problem?
>
> Going to a Newsgroup to get what usually takes a few YEARS of college
> and experience does not work.
>
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