Re: Inflate a boolean

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At 00:35 2005-02-21, Tony Bowden wrote:
> > >That is entirely subjective, and most definitely poor design (in my
> > >opinion) in many cases.
> > Me too. Possibly there would be a value table for that to achieve 3NF.
>
>A table that maps the key "yes" to the value "yes", and the key "no"
>to the value "no"?

Depends. For a boolean value, probably no. For other sets of values, 
possibly yes. Depends on the application. Depends on what you use the 
database for.

For example, let's say I have an Order Type with values like "Credit Card", 
"Wire Order", and fifteen other things. I wouldn't use a varchar(30) for 
that, I would use an "order_type_id int" field and a value table with the 
values "Credit Card", "Wire Order", etc if many different applications on 
top of the database would need to know about this. If there's only one 
application doing this, maybe the mapping would go into the application, 
like the OP intends to do with the boolean <-> yes/no value.

The boolean example is a bit minimal. But I wouldn't store "YES" or "NO" in 
a varchar field.


/J

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