Re: cursor MOVE vs OFFSET in SELECT

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От Grzegorz Jaśkiewicz
Тема Re: cursor MOVE vs OFFSET in SELECT
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Msg-id 2f4958ff0910260334r2bec490cq6f0181fb317fdc36@mail.gmail.com
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Ответ на cursor MOVE vs OFFSET in SELECT  (silly8888 <silly8888@gmail.com>)
Ответы Re: cursor MOVE vs OFFSET in SELECT  (silly8888 <silly8888@gmail.com>)
Re: cursor MOVE vs OFFSET in SELECT  (Pavel Stehule <pavel.stehule@gmail.com>)
Список pgsql-general


On Mon, Oct 26, 2009 at 10:30 AM, silly8888 <silly8888@gmail.com> wrote:
Suppose that you have a query, say $sql_query, which is very
complicated and produces many rows. Which of the following is going to
be faser:

   $sql_query OFFSET 3000 LIMIT 12;

or

   BEGIN;
   DECLARE cur1 CURSOR FOR $sql_query;
   MOVE 3000 IN cur1;
   FETCH 12 FROM cur1;
   COMMIT;

Naturally, the former cannot be slower than the latter. So my question
essentially is whether the MOVE operation on a cursor is
(significantly) slower that a OFFSET on the SELECT.


OFFSET/LIMIT. Afaik cursor always fetches everything.
 

--
GJ

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