Re: surrogate key or not?

On Friday 23 July 2004 04:47 pm, Michael Glaesemann wrote:

> > id serial unique
> > name varchar(25) not null
> > primary key is name - after all, you are going to search this on name
> > arent
> > you? or is there some advantage in doing it your way?
>
> Also, your explanation "after all, you are going to search..." did not
> mention row uniqueness at all. Sorry if this is not what you meant, but
> I can only go by what you've written.

ok, i'll rephrase the whole thing:

i have a master table with two fields:
id serial unique
name varchar not null (and will be unique)

i always make 'name' the primary key, and since it is the primary key, i dont
explicitly specify it as unique, and after postgres 7.3 came out, i have
added the 'unique' constraint to the 'id'

on looking at the gnumed schema, i saw that although 'name' was unique, the
serial key, 'id' was made the primary key. So i wondered why and whether
there were advantages in doing it this way.
--
regards
kg

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