Re: 2 versions of an entity worth distinct table?

gvimrc(at)gmail(dot)com (gvim) writes:
> If a table representing contact details can have 2 but no more than 2 email addresses is it really worth factoring-out email addresses to a separate table. Technically it's a 1-to-many relationship so should be done this way but what is the general practice out there in such "max. 2" situations? Keeping them as:
>
> Primary Email
> Secondary Email
>
> .... also preserves priority though not strictly normalised, I know.

I'd be inclined to normalize this, as it's:

a) difficult to guarantee that it will only ever be 2.

b) mighty nice to be able to attach validation rules to ONE simple email
table, rather than having to put them on several columns possibly
spread across more tables.
--
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