Re: are cursors necessary?
От | Richard Huxton |
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Тема | Re: are cursors necessary? |
Дата | |
Msg-id | 200312042331.18616.dev@archonet.com обсуждение исходный текст |
Ответ на | are cursors necessary? (Mark Harrison <mh@pixar.com>) |
Ответы |
Re: are cursors necessary?
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Список | pgsql-general |
On Thursday 04 December 2003 22:46, Mark Harrison wrote: > res = PQexec(conn, "BEGIN"); > res = PQexec(conn, "DECLARE myportal CURSOR FOR select * from > pg_database"); res = PQexec(conn, "FETCH ALL in myportal"); > res = PQexec(conn, "CLOSE myportal"); > res = PQexec(conn, "END"); > Is there any value in my own query-only programs to declaring the cursor > for each search? Well - if you want to scroll forward/backward through the resultset, you'd want a cursor. Or, if your client had limited memory and the resultset was large you might want to do so. PG will return all rows at once, so if your SELECT returns 5 million rows you'll use a lot of RAM on the client side. -- Richard Huxton Archonet Ltd
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