Re: Question on creating keys on partitioned tables

Siddharth Jain <siddhsql@gmail.com> writes:
> I think the two are equivalent. If not, could you please explain why?

Well, they're formally equivalent if you require there to be only one
X value per partition (ie, PARTITION BY LIST with only one listed value
per partition); if there's more, they're not the same thing.

Neither one guarantees that Y is globally unique.  We have no mechanism
for enforcing uniqueness across partitions except for partition key
columns.

                        regards, tom lane