Re: PostgreSQL 8.3, libpq and WHERE CURRENT OF

Forget this one, just missing the WITH HOLD option...
Must teach myself a bit more before sending further mails.
Seb

Sebastien FLAESCH wrote:
> Ok...
>
> Tested with 8.2.3:
>
> Actually you can't DECLARE a cursor outside a transaction:
>
> test1=> declare c1 cursor for select * from dbit2;
> ERROR: DECLARE CURSOR may only be used in transaction blocks
>
> That's the main reason why we don't use DECLARE CURSOR...
>
> I understand we could use DECLARE CURSOR when a FOR UPDATE is
> detected, to allow UPDATE/DELETE WHERE CURRENT OF - these only
> make sense inside a transaction...
>
> But for normal cursors, we need to support multiple active result
> sets that can last outside a transaction block.
>
> Basically, we need all what you can do with ODBC cursors.
>
> Anyway, thanks for your help.
>
> Seb
>
> Tom Lane wrote:
>> Sebastien FLAESCH <sf(at)4js(dot)com> writes:
>>> Does a simple PQPrepare() with a SELECT statement not create a cursor on
>>> the server side?
>>
>> No. A prepared statement is just a query plan, not a query-in-progress.
>>
>> The Bind/Execute messages sent by PQexecPrepared create something akin
>> to a cursor, but libpq doesn't expose any API for fetching one row at a
>> time in that context, so there's no way to use the "current row" anyway.
>>
>> regards, tom lane
>>
>
>