Re: Unique contraints vs. Unique indexes

On Fri, 10 Aug 2001 22:00:54 GMT, "Robert Fazio" <rfazio_at_home.com.nospam> wrote:

>Do you really mean non_unique? A PK is a PK. You either want all of the
>fields at creation and you want them to be unique or you don't.
>
>The only difference between a UK and a PK is that UK's don't have to have
>all fields supplied (i.e. Some can be null).
>
>--
>Robert Fazio
>Senior Technical Analyst
>dbabob_at_yahoo.com
>
>"James Williams" <techsup_at_mindspring.com> wrote in message
>news:3b744034.170930734_at_nntp.mindspring.com...
>> I am about to build a data warehouse that will eventually be 1 TB.
>>
>>
>> A PK's are going to have non_unique indexes and so that they can be
>> deferrable.
>>
>>
>> What are the heavy hitters opinions on this?
>
>

My point was I plan to create the tables and then create non_unique indexes over the column that will serve as the PK for each table. Then I would ALTER TABLE xxx ADD PRIMARY KEY and this should cause a PK where the uniqueness would be determined at commit. The same would be the case with UNIQUE constraints.

I am curious about issues others may experienced with this approach. Received on Mon Aug 13 2001 - 06:41:06 CDT