Re: Updateable cursors patch - Mailing list pgsql-patches

Correction....  Meant to say

According to the standard, updateable cursors cannot be scrollable until
we have full cursor update.

FAST PostgreSQL wrote:
> Right. The current implementation allows only simple queries. Joins are
> disallowed. According to the standard, updateable cursors cannot be
> scrollable. So maybe I should put an explicit check during cursor
> creation disallowing scrollable updateable cursors.
>
> Rgds,
> Arul Shaji
>
>
> Pavel Stehule wrote:
>> 2007/5/18, FAST PostgreSQL <fastpgs@fast.fujitsu.com.au>:
>>> No. It works with scrollable cursors. It will work for cursors/selects
>>> which does not put the results in some store, such as WITH hold/group
>>> by/order by etc.... But most of these restrictions apply for normal
>>> 'Select for update' anyway. (With the order by clause, the
>>> implementation is as per the sql standards.)
>>
>> some scrollable cursors are materialised. It depends on query :-(.
>> Simple query without join can works.
>>
>> regards
>>
>> Pavel
>>
>>>
>>> I can update the documentation once the initial review is done and what
>>> I have done gets atleast a pass mark :-)
>>>
>>> Rgds,
>>> Arul Shaji
>>>
>>>
>>> Pavel Stehule wrote:
>>> > Hello
>>> >
>>> > I am not sure, but your solution will faill on scrollable cursors
>>> > (it's similar to holdable cursors). I miss part about limits in
>>> > documentation. Propably updatable cursors aren't supported by plpgsql
>>> > (and it's point to ToDo).
>>> >
>>> > Regards
>>> > Pavel Stehule
>>> >
>>> > 2007/5/17, FAST PostgreSQL <fastpgs@fast.fujitsu.com.au>:
>>> >> Attached is an updated version of the updateable cursors patch
>>> against
>>> >> the latest cvs head.
>>> >>
>>> >> Most of the changes in the patch are to make it sync with the
>>> changes in
>>> >> CVS recently, for DECLARE CURSOR and EXPLAIN, as mentioned by
>>> Jaime in
>>> >> his mail below.
>>> >>
>>> >> Rgds,
>>> >> Arul Shaji
>>> >>
>>> >>
>>> >> FAST PostgreSQL wrote:
>>> >> > Right. I will send an updated patch against the CVS head in the
>>> next
>>> >> > couple of days.
>>> >> >
>>> >> > Jaime Casanova wrote:
>>> >> >> On 4/4/07, FAST PostgreSQL <fastpgs@fast.fujitsu.com.au> wrote:
>>> >> >>> Attached is a working updateable cursors patch. The core
>>> >> >>> functionality has
>>> >> >>> been implemented and the patch also contains the regression
>>> tests and
>>> >> >>> documentation.
>>> >> >>>
>>> >> >>
>>> >> >> this one doesn't apply cleanly to HEAD because of the changes in
>>> >> >>
>>> http://archives.postgresql.org/pgsql-committers/2007-04/msg00447.php
>>> >> >>
>>> >> >
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