Re: CHECK versus a Table for an enumeration

On 22/12/2003 21:37 Melanie Bergeron wrote:
> Hi all!
>
> I want to know what's better between these 2 solutions :
>
> CREATE TABLE user (
> ...
> user_type   text     CHECK(user_type='Root' OR user_type = 'Admin' OR
> user_type = 'Standard'));
>
> or the following :
>
> CREATE TABLE user_type(
> user_type_id     integer   PRIMARY KEY,
> user_type_desc text);
>
> CREATE TABLE user (
> ...
> user_type_id   integer,
> CONSTRAINT user_type_exists FOREIGN KEY (user_type_id) REFERENCES
> user(user_type_id));
>
> I am really confused so I'll wait for your advices.
>
> Thanks,
>
> Melanie

just my personal opinion but here goes:

For the example you've provided I don't think theres much in it. The
second version would give you ability to change the text of the user type
if that were important and to add new user types without having to alter
constraints. So if I _had_ to choose, I'd take the second option.

HTH

--
Paul Thomas
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