Re: A thought on Index Organized Tables

[Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>]

Gokulakannan Somasundaram <gokul007(at)gmail(dot)com> writes:
> a) We are already going from table to index to do unique checks. This is the
> same thing, which we will do to go and update the snapshot in the indexes.

No, it is not the same thing.  Updating index snapshots requires being
able to *re-find* a previously made index entry for the current row.
And it has to be done 100% reliably.  The worst that happens if an index
entry is not found when it should be during a uniqueness check is that
the uniqueness constraint is not enforced properly; which is bad but it
doesn't lead to internally-inconsistent data structures.

> b) The way, it should work would be to have a check on whether the operator
> is broken / function is volatile and put the onus on the user to make sure
> that they are updated correctly.

Pretending the problem doesn't exist doesn't make it go away ...

			regards, tom lane