On 2009-10-09, Peter Eisentraut <peter_e(at)gmx(dot)net> wrote:
> On Fri, 2009-10-09 at 11:46 -0700, Christophe Pettus wrote:
>> Domains are basically type aliases with an optional CHECK clause, so
>> you could do something like:
>>
>> CREATE DOMAN sales_tax_rate AS DECIMAL(5,5) CHECK (VALUE >= 0);
>>
>> Then, you can use the type "sales_tax_rate" in your tables, etc. just
>> as a normal first-class type. (The only limitation, right now, is
>> that you can't create an array of them.)
>
> Actually I wouldn't bother with the precision and scale at all. I'd go
> with something like
>
> CREATE DOMAN sales_tax_rate AS DECIMAL CHECK (VALUE >= 0 AND VALUE <=1);
why the latter check ( VALUE <=1 )?