| From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
|---|---|
| To: | Gokulakannan Somasundaram <gokul007(at)gmail(dot)com> |
| Cc: | Heikki Linnakangas <heikki(dot)linnakangas(at)enterprisedb(dot)com>, pgsql-hackers list <pgsql-hackers(at)postgresql(dot)org>, Greg Stark <gsstark(at)mit(dot)edu>, Karl Schnaitter <karlsch(at)gmail(dot)com> |
| Subject: | Re: A thought on Index Organized Tables |
| Date: | 2010-02-28 15:47:54 |
| Message-ID: | 8512.1267372074@sss.pgh.pa.us |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
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
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Joachim Wieland | 2010-02-28 15:56:28 | Re: Re: Hot Standby query cancellation and Streaming Replication integration |
| Previous Message | Bruce Momjian | 2010-02-28 15:13:56 | Re: [GENERAL] trouble with to_char('L') |