Re: libpqxx: Cursors needed??!
От | Jeroen T. Vermeulen |
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Тема | Re: libpqxx: Cursors needed??! |
Дата | |
Msg-id | 20030119141713.GC84000@xs4all.nl обсуждение исходный текст |
Ответ на | libpqxx: Cursors needed??! ("Key88 SF" <key88sf@hotmail.com>) |
Список | pgsql-interfaces |
On Wed, Jan 15, 2003 at 10:51:22PM +0000, Key88 SF wrote: > > It's not clear to me when to use the Cursor class, if at all. Transactions > seem to execute fine and I get valid Result classes back without using > cursors. There's no special reason why you should use Cursor to retrieve results--you can always just call TransactionItf::Exec() and get Results from that. Use Cursor only when you want to create an SQL cursor. > Many of the sample programs don't use them either. The sample programs were mostly written in the order in which they're numbered, so some of them predate cursors. > Are cursors needed at all?? No. It's a convenience class; you can always just execute the cursor-related commands by hand. The wrapper class just gives you conveniences like additional compiler checking, more specific error messages, more user-friendly syntax, and absolute positioning. The latter may be a little harder to do for yourself than it seems, because of the way postgres returns tuple counts when moving or fetching with a cursor. Jeroen
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