Hi Jens, I have tried with fetch size of 10000 still its not giving any results. My expectations were that Cassandra can handle a million rows easily.
Is there any mistake in the way I am defining the keys or querying them. Thanks Mehak On Wed, Mar 18, 2015 at 3:02 AM, Jens Rantil <jens.ran...@tink.se> wrote: > Hi, > > Try setting fetchsize before querying. Assuming you don't set it too high, > and you don't have too many tombstones, that should do it. > > Cheers, > Jens > > – > Skickat från Mailbox <https://www.dropbox.com/mailbox> > > > On Wed, Mar 18, 2015 at 2:58 AM, Mehak Mehta <meme...@cs.stonybrook.edu> > wrote: > >> Hi, >> >> I have requirement to fetch million row as result of my query which is >> giving timeout errors. >> I am fetching results by selecting clustering columns, then why the >> queries are taking so long. I can change the timeout settings but I need >> the data to fetched faster as per my requirement. >> >> My table definition is: >> *CREATE TABLE images.results (uuid uuid, analysis_execution_id varchar, >> analysis_execution_uuid uuid, x double, y double, loc varchar, w double, h >> double, normalized varchar, type varchar, filehost varchar, filename >> varchar, image_uuid uuid, image_uri varchar, image_caseid varchar, >> image_mpp_x double, image_mpp_y double, image_width double, image_height >> double, objective double, cancer_type varchar, Area float, submit_date >> timestamp, points list<double>, PRIMARY KEY ((image_caseid),Area,uuid));* >> >> Here each row is uniquely identified on the basis of unique uuid. But >> since my data is generally queried based upon *image_caseid *I have made >> it partition key. >> I am currently using Java Datastax api to fetch the results. But the >> query is taking a lot of time resulting in timeout errors: >> >> Exception in thread "main" >> com.datastax.driver.core.exceptions.NoHostAvailableException: All host(s) >> tried for query failed (tried: localhost/127.0.0.1:9042 >> (com.datastax.driver.core.exceptions.DriverException: Timed out waiting for >> server response)) >> at >> com.datastax.driver.core.exceptions.NoHostAvailableException.copy(NoHostAvailableException.java:84) >> at >> com.datastax.driver.core.DefaultResultSetFuture.extractCauseFromExecutionException(DefaultResultSetFuture.java:289) >> at >> com.datastax.driver.core.DefaultResultSetFuture.getUninterruptibly(DefaultResultSetFuture.java:205) >> at >> com.datastax.driver.core.AbstractSession.execute(AbstractSession.java:52) >> at QueryDB.queryArea(TestQuery.java:59) >> at TestQuery.main(TestQuery.java:35) >> Caused by: com.datastax.driver.core.exceptions.NoHostAvailableException: >> All host(s) tried for query failed (tried: localhost/127.0.0.1:9042 >> (com.datastax.driver.core.exceptions.DriverException: Timed out waiting for >> server response)) >> at >> com.datastax.driver.core.RequestHandler.sendRequest(RequestHandler.java:108) >> at >> com.datastax.driver.core.RequestHandler$1.run(RequestHandler.java:179) >> at >> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) >> at >> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) >> at java.lang.Thread.run(Thread.java:744) >> >> Also when I try the same query on console even while using limit of 2000 >> rows: >> >> cqlsh:images> select count(*) from results where >> image_caseid='TCGA-HN-A2NL-01Z-00-DX1' and Area<100 and Area>20 limit 2000; >> errors={}, last_host=127.0.0.1 >> >> Thanks and Regards, >> Mehak >> >> >> >> >> >> >
