Unique Primary Index restricted in PPI

UDA

Unique Primary Index restricted in PPI

Hi All,

I was reading through a few Teradata material and came across this statement:

"Unique Primary Index cannot be defined when  the partition column is nor part of Primary Index" .

And my questions is : WHY ??? I checked with a few serior colleques and all of have the same question. Why ?

I believe that there is nothing wrong in defining Unique Primary index when PPI is defined, though it might not add much value. But why did Teradata enforce this restriction ?

- Jais

2 REPLIES
Enthusiast

Re: Unique Primary Index restricted in PPI

This was discussed to death some time ago on another thread in this forum:

http://forums.teradata.com/forum/database/ppi-0

The short answer is that it would be too expensive to enforce uniqueness constraint.

Re: Unique Primary Index restricted in PPI

Thanks Jim. I got it. Nice to the see the patient sharing nature(in the above mentioned thread) of Teradata geeks. :-)