Re: [RFC] libpq extensions - followup
От | Iker |
---|---|
Тема | Re: [RFC] libpq extensions - followup |
Дата | |
Msg-id | 00c101c2c50a$c707fed0$6401a8c0@KNUTH обсуждение исходный текст |
Ответ на | Re: [RFC] libpq extensions - followup (Iker Arizmendi <iker@research.att.com>) |
Список | pgsql-general |
BTW, the source tarball contains two example programs - an event-driven version which demonstrates simulating multiple "in-flight" queries and a multi-threaded version. Cheers, Iker ----- Original Message ----- From: "Iker Arizmendi" <iker@research.att.com> Newsgroups: comp.databases.postgresql.general,comp.databases.postgresql.questions Sent: Sunday, January 26, 2003 2:02 AM Subject: Re: [RFC] libpq extensions - followup > Althought multiple queries can't be executed concurrently they can be > queued up by a connection object. For instance: > > PGXquery* q1 = PQXcreateQuery(...); > PGXquery* q2 = PQXcreateQuery(...); > ... > PGXquery* qN = PQXcreateQuery(...); > > PQXexecute(conn1, q1); > PQXexecute(conn1, q2); > ... > PQXexecute(conn1, qN); > > while (1) { /* event loop code */ } > > In this example, queries q1 through qN are "in flight" simultaneously as > far as the client is concerned even though the connection conn1 is > really queueing them up. During execution of the event loop, the > connection object manages the job of executing each query > sequentially (which, with respect to the client, is an implementation > detail). > > Cheers, > Iker > > On Sun, 26 Jan 2003 00:47:20 -0500 > Tom Lane <tgl@sss.pgh.pa.us> wrote: > > > Iker Arizmendi <iker@research.att.com> writes: > > > A while back I suggested that it would be useful if asynchronous > > > connections could support multiple queries "in flight", especially > > > if you're working on event driven applications (see topic "rfc - > > > libpq extensions"). I've since started work on a simple library, > > > > I must be missing something fundamental here. The backend doesn't > > support multiple parallel queries, so how can you have "multiple > > queries in flight" on the same connection? > > > > regards, tom lane > > > ---------------------------(end of broadcast)--------------------------- > TIP 2: you can get off all lists at once with the unregister command > (send "unregister YourEmailAddressHere" to majordomo@postgresql.org)
В списке pgsql-general по дате отправления: