Re: Ask ctid - Mailing list pgsql-general

From Achmad Nizar Hidayanto
Subject Re: Ask ctid
Date
Msg-id 47D0FC9C.5030502@cs.ui.ac.id
Whole thread Raw
In response to Re: Ask ctid  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Ask ctid  (Martijn van Oosterhout <kleptog@svana.org>)
Re: Ask ctid  (Alban Hertroys <dalroi@solfertje.student.utwente.nl>)
List pgsql-general
Thank you for the comment,

I just wonder, how come i have two identic rows. I have set the primary key and set it as a unique. That's why i take
a look at ctid (in real, i don't use this id. I just tried to trace why i have two identic rows. After examining the physical
id using ctid, i found that the two identic rows differ in their ctid).

Having this case, can i conclude that postgre cannot guarantee the uniqueness of primary key? or is it just a bug of old
version of postgre?

Many thanks for your help.


Nizar
=====

Tom Lane wrote:
Achmad Nizar Hidayanto <nizar@cs.ui.ac.id> writes: 
I implement database in my faculty using Postgre. I have a problem
with ctid in my tables. Let say, i have table STUDENT with #STU
as the primary key. I don't know what happend in this table, some
rows have exactly the same value ( i also have set the #STU as unique).
After tracing the table,  i found that the two rows differ in ctid value.
As the impact, my application cannot operate well.   
There are some known bugs in older PG releases that could lead to
duplicate rows (actually, to multiple versions of a row all being seen
as live).  If you're not on the latest minor version of your release
series, update.
		regards, tom lane
 

pgsql-general by date:

Previous
From: "Anirban Banerjee"
Date:
Subject: Re: staring pgsql on fedora 8
Next
From: "Anton Melser"
Date:
Subject: Re: shared_buffers and shmmax what are the max recommended values?