Sorry must read "fetched" in title.
Similar question:
When execution a SELECT (returning a large result set):
Is the whole result set fetched to the client app, not matter what row number is provided to the first PQgetvalue()
call(or similar API call on
result set data or meta-data)?
Seb
On 8/29/19 6:32 PM, Sebastien FLAESCH wrote:
> Hi all,
>
> We are using libpq in our C program.
>
> I was wondering how the client lib / protocol manage to fetch the result set to the client app memory.
>
> Is there some optimization ?
>
> Are rows fetched in sequence until the requested row?
>
> I mean if I do a SELECT that produces a huge result set, and then call PQgetvalue() with a row_number = 5000, are all
5000rows fetched from the
> server or is there some smart fast-forward done because I did not ask the 4999 previous rows?
>
> We know about server cursors (declare + fetch forward), and we do already fetch blocks of rows with this.
>
> But server cursors are slow (and certainly use more server resources), compared to direct SELECT execution.
>
> So we are wondering what would be the impact in terms of resources on the client application.
>
> Is there any doc link or blog that would explain best practices with libpq result set programming?
>
> Thanks!
> Seb
>
>
