Hi Sorin, Thanks very much for your response. From the sounds of it I think I can share the prepared statements as long as I handle the case when they disappear (out of LSU cache or due to server restart). To identify this I think I need to catch InvalidRequestException and look at the message (I will do some investigation on Monday and post an update if I figure out the exact messages).
Regards, Stuart On Fri, Apr 19, 2013 at 11:23 PM, Sorin Manolache <sor...@gmail.com> wrote: > On 2013-04-19 13:57, Stuart Broad wrote: > >> Hi, >> >> I am using Cassandra.Client >> prepare_cql3_query/execute_**prepared_cql3_query to create and run some >> prepared statements. It is working well but I am unclear as to how long >> the server side 'caches' the prepared statements. Should a prepared >> statement be prepared for every new Cassandra.Client? Based on my >> limited testing it seems like I can create some prepared statements in >> one Cassandra.Client and use in another but I am not sure how >> reliable/lasting this is i.e. If I called the prepared statement again >> the next day would it still exist? What about if cassandra was >> re-started? >> > > I don't know the answer and I have the same question. But have a look at > this discussion, dating from September 2012. > > https://issues.apache.org/**jira/browse/CASSANDRA-4449<https://issues.apache.org/jira/browse/CASSANDRA-4449> > > Apparently prepared statements are shared among threads (they were > per-connection previously), they don't survive server restarts, apparently > there's an LRU mechanism, and apparently you get a special exception if the > prepared statement "disappeared" so you can prepare it again. > > Regards, > Sorin > > > _Background:_ >> >> I am creating prepared statements for batch updates of pre-defined >> lengths (e.g. 10000, 1000, 500, 250, 50, 10, 1) and wanted to know if >> these could just be set up once. We felt that using the prepared >> statements was easier than escaping values within a CQL statement and >> probably more performant. >> >> Thanks in advance for your help. >> >> Regards, >> >> Stuart >> >> p.s. I am relatively new to cassandra. >> > >
