Also, make sure you're using prepared statements. -- Colin 320-221-9531
> On May 25, 2014, at 1:56 PM, "Jack Krupansky" <j...@basetechnology.com> wrote: > > Typo: I presume “channelid” should be “tagid” for the partition key for your > table. > > Yes, BATCH statements are the way to go, but be careful not to make your > batches too large, otherwise you could lose performance when Cassandra is > relatively idle while the batch is slowly streaming in to the coordinator > node over the network. Better to break up a large batch into multiple > moderate size batches (exact size and number will vary and need testing to > deduce) that will transmit quicker and can be executed in parallel. > > I’m not sure Cassandra on a laptop would be the best measure of performance > for a real cluster, especially compared to a server with more CPU cores than > your laptop. > > And for a real cluster, rows with different partition keys can be sent to a > coordinator node that owns that partition key, which could be multiple nodes > for RF>1. > > -- Jack Krupansky > > From: Mark Farnan > Sent: Sunday, May 25, 2014 9:36 AM > To: user@cassandra.apache.org > Subject: Possible to Add multiple columns in one query ? > > I’m sure this is a CQL 101 question, but. > > Is it possible to add MULTIPLE Rows/Columns to a single Partition in a > single CQL 3 Query / Call. > > Need: > I’m trying to find the most efficient way to add multiple time series events > to a table in a single call. > Whilst most time series data comes in sequentially, we have a case where it > is often loaded in bulk, say sent 100,000 points for 50 channels/tags at > one go. (sometimes more), and this needs to be loaded as quickly and > efficiently as possible. > > Fairly standard Time-Series schema (this is for testing purposes only at this > point, and doesn’t represent final schemas) > > CREATE TABLE tag ( > tagid int, > idx timestamp, > value double, > PRIMARY KEY (channelid, idx) > ) WITH CLUSTERING ORDER BY (idx DESC); > > > Currently I’m using Batch statements, but even that is not fast enough. > > Note: At this point I’m testing on a single node cluster on laptop, to > compare different versions. > > We are using DataStax C# 2.0 (beta) client. And Cassandra 2.0.7 > > Regards > Mark.
