Re: How to create a cursor that is independent of transactions and doesn't calculated when created ?

boraldomaster wrote
>
> David Johnston wrote
>> Your original examples only create the cursor and do not actually use it.
>> You should be comparing how long it takes both examples to fetch the
>> first 10 pages of records to get a meaningful comparison.  It won't
>> matter if the DECLARE only takes 3ms in the non-hold case if retrieving
>> the first page of records take 2s.
> Certainly -
*
> close all;
> begin;
> declare mycursor cursor for select * from z order by name;
> fetch 10 from mycursor;
> commit;
*
>  - takes 3 ms all.
> Each
*
> fetch 10 from mycursor
*
>  takes 1-2 ms.
> So this is perfectly optimized in transaction. And I wonder why isn't it
> optimized for a whole session.

I am sorry I cannot answer this kind of "why was it implemented in
such-and-such way" question.  Maybe someone from the core programming team
will chime in.

David J.







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