Re: bidirectional cursors on views

From: Shachar Shemesh <psql(at)shemesh(dot)biz>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: Hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: bidirectional cursors on views
Date: 2003-08-17 19:28:31
Message-ID: 3F3FD75F.1020509@shemesh.biz
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

Tom Lane wrote:

>Shachar Shemesh <psql(at)shemesh(dot)biz> writes:
>
>
>>When I try to open (using MFC) a non-forward only cursor on a view (i.e.
>>- select * from viewname), I get an error of "attribute ctid not found".
>>There are some chances that this is an ODBC problem, but my research
>>suggests that the dependancy on ctid is created by the database itself.
>>
>>
>
>Your research is faulty --- it's an ODBC issue.
>
>
Am I to understand that psql's nativ cursors support bidirectional
movements on views? That is good news, actually.

>>Can anyone comment about this? Is this problem solveable?
>>
>>
>
>You'd have better luck asking on pgsql-odbc, but my guess is that they
>depend on ctid as a (crude) form of unique row identification.
>
That was my guess as well. I did ask at pgsql-odbc on Wendsday. When
noone answered, I did the open source thing and tried to singstep the
code. Thing is - I placed a breakpoint on all occurances of "ctid" in
the ODBC driver's code, and none of those breakpoints were hit when the
query that didn't go through was sent. That's the reason I arrived at
the conclusion I did.

If you can tell me for sure that such cursors are, in fact, supported by
pgsql itself, then I'll go back to the odbc sources and, if necessary,
implement this (not happy about those prospects - I don't know ODBC
worth of manure).

> regards, tom lane
>
>
Many thanks,

Shachar

--
Shachar Shemesh
Open Source integration consultant
Home page & resume - http://www.shemesh.biz/

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Tom Lane 2003-08-17 22:25:08 Re: 7.4 beta 1 getting out of swap
Previous Message Rod Taylor 2003-08-17 18:58:48 Re: DOMAIN NEED CAST ?