Re: get all row keys of a table using CQL3

hi Blake, arh okay, token function is nice. But I am still bit confused by the word "page through all rows" select id from mytable where token(id) > token(12345) it will return all rows whose partition key's corresponding token that is > 12345 ? I guess my question #1 still there, that does this q

Re: get all row keys of a table using CQL3

Hi Jimmy, Check out the token function: http://www.datastax.com/docs/1.1/dml/using_cql#paging-through-non-ordered-partitioner-results You can use it to page through your rows. Blake On Jul 23, 2013, at 10:18 PM, Jimmy Lin wrote: > hi, > I want to fetch all the row keys of a table using CQL3:

get all row keys of a table using CQL3

hi, I want to fetch all the row keys of a table using CQL3: e.g select id from mytable limit 999 #1 For this query, does the node need to wait for all rows return from all other nodes before returning the data to the client(I am using astyanax) ? In other words, will this operation create a

disappointed

I want to check in. I'm sad, mad and afraid. I've been trying to get a 1.2 cluster up and working with my data set for three weeks with no success. I've been running a 1.1 cluster for 8 months now with no hiccups, but for me at least 1.2 has been a disaster. I had high hopes for leveraging t

unable to compact large rows

I'm getting constant exceptions during compaction of large rows. In fact, I have not seen one work, even starting from an empty DB. As soon as I start pushing in data, when a row hits the large threshold, it fails compaction with this type of stack trace: INFO [CompactionExecutor:6] 2013-07-

Re: Decommission an entire DC

All you need to do is to decrease the replication factor of DC1 to 0, and then decommission the nodes one by one, I've tried this before and it worked with no issues. Thanks, On Tue, Jul 23, 2013 at 10:32 PM, Lanny Ripple wrote: > Hi, > > We have a multi-dc setup using DC1:2, DC2:2. We want to

Re: Representation of dynamically added columns in table (column family) schema using cqlsh

See this as this was discussed earlier: http://cassandra-user-incubator-apache-org.3065146.n2.nabble.com/Representation-of-dynamically-added-columns-in-table-column-family-schema-using-cqlsh-td7588997.html Regards, Shahab On Fri, Jul 12, 2013 at 11:13 AM, Shahab Yunus wrote: > A basic question

Re: Unable to describe table in CQL 3

Rahul, See this as it was discussed earlier: http://cassandra-user-incubator-apache-org.3065146.n2.nabble.com/Representation-of-dynamically-added-columns-in-table-column-family-schema-using-cqlsh-td7588997.html Regards, Shahab On Tue, Jul 23, 2013 at 2:51 PM, Rahul Gupta wrote: > I am using C

Re: cassandra 1.2.6 -> Start key's token sorts after end token

Oh, and in the past 0.20.x has been pretty stable by the wayŠ..they finally switched their numbering scheme thank god. Dean On 7/23/13 2:13 PM, "Hiller, Dean" wrote: >Perhaps try 0.20.2 as > > 1. The maven pom files have cassandra depending on 0.20.2 > 2. The 0.20.2 default was murmur and we

Re: cassandra 1.2.6 -> Start key's token sorts after end token

Perhaps try 0.20.2 as 1. The maven pom files have cassandra depending on 0.20.2 2. The 0.20.2 default was murmur and we had to change it to random partitioner or it wouldn't work for us Ie. I suspect they will change the pom file to a more recent version of hadoop at some point but I wonder

Re: cassandra 1.2.6 -> Start key's token sorts after end token

Dean, I am using hadoop 1.0.3. Indeed, using Cassandra 1.2.3 with Random partitioner, it worked. However, it's the only reason for me to use randompartitioner, I really would like to move forward. Besides, I tried to use Cassandra 1.2.6 with RandomPartitioner and I got problems when insert

Decommission an entire DC

Hi, We have a multi-dc setup using DC1:2, DC2:2. We want to get rid of DC1. We're in the position where we don't need to save any of the data on DC1. We know we'll lose a (tiny. already checked) bit of data but our processing is such that we'll recover over time. How do we drop DC1 and just m

Re: sstable size change

"Will Cassandra force any newly compacted files to my new setting as compactions are naturally triggered" Yes. Let it compact and increase in size. On Tue, Jul 23, 2013 at 9:38 AM, Robert Coli wrote: > On Tue, Jul 23, 2013 at 6:48 AM, Keith Wright wrote: > >> Can you elaborate on what you mean

Unable to describe table in CQL 3

I am using Cassandra ver 1.1.9.7 Created a Column Family using Cassandra-cli. create column family events with comparator = 'CompositeType(DateType,UTF8Type)' and key_validation_class = 'UUIDType' and default_validation_class = 'UTF8Type'; I can describe this CF using CQL2 but getting error when

Re: Are Writes disk-bound rather than CPU-bound?

Also, thinking about it more….. There are constant write loads where if the cluster is big enough compared to the write load that the flushes are not happening that often causing a profile like that to be cpu bound. In my mind it really is about what configuration you have. If I have a high writ

Re: Are Writes disk-bound rather than CPU-bound?

Out of curiosity, isn't what is really happening is this "As writes keep coming in, memory fills up causing flushes to the commit log disk of the whole memtable. In a bursting scenario, writes are thus limited only by memory and cpu in short bursting cases that tend to fit in memory. In a mor

Re: Are Writes disk-bound rather than CPU-bound?

I see pretty much the same formulation in the 1.2 docs, so I'm wondering what would be the best rewrite of that paragraph? On Tue, Jul 23, 2013 at 9:00 AM, hajjat wrote: > > > On Tue, Jul 23, 2013 at 5:05 AM, aaron morton [via [hidden > email]

Re: About column family

We use PlayOrm to have 60,000 VIRTUAL column families such that the performance is just fine ;). You may want to try something like that. Dean From: Robert Coli mailto:rc...@eventbrite.com>> Reply-To: "user@cassandra.apache.org" mailto:user@cassandra.apache.or

Re: Safely adding new nodes without losing data

On Sat, Jul 20, 2013 at 7:30 AM, E S wrote: > I am trying to understand the best procedure for adding new nodes. The > one that I see most often online seems to have a hole where there is a low > probability of permanently losing data. I want to understand what I am > missing in my understand

Re: About column family

On Tue, Jul 23, 2013 at 3:23 AM, bjbylh wrote: > 1,how many column families can be created in a cluster?is there a limit to > the number of it? > Low number of hundreds is highest practical. The limit in practice is amount of heap, each CF consumes heap. > 2,it spents 2-5 seconds to create a n

Re: sstable size change

On Tue, Jul 23, 2013 at 6:48 AM, Keith Wright wrote: > Can you elaborate on what you mean by "let it take its own course > organically"? Will Cassandra force any newly compacted files to my new > setting as compactions are naturally triggered? > You see, when two (or more!) SSTables love each o

high write load, with lots of updates, considerations? tomestombed data coming back to life

I was watching some videos from the C* summit 2013 and I recall many people saying that if you can some up with a design where you don't preform updates on rows, that would make things easier (I believe it was because there would be less compaction). When building an Analytics (time series) app on

Re: funnel analytics, how to query for reports etc.

Thanks Aaron. Too bad Rainbird isn't open sourced yet! On Tue, Jul 23, 2013 at 4:48 AM, aaron morton wrote: > For background on rollup analytics: > > Twitter Rainbird > http://www.slideshare.net/kevinweil/rainbird-realtime-analytics-at-twitter-strata-2011 > Acunu http://www.acunu.com/ > > Cheer

Re: Are Writes disk-bound rather than CPU-bound?

On Tue, Jul 23, 2013 at 5:05 AM, aaron morton [via cassandra-u...@incubator.apache.org] < ml-node+s3065146n7589236...@n2.nabble.com> wrote: > “/Insert-heavy workloads will actually be CPU-bound in Cassandra before > being > memory-bound/” > > What is the source for that ? http://www.datastax.com

Re: NPE in CompactionExecutor

I'm running the latest from the 1.2 branch as of a few days ago. I needed one of the patches that will be in 1.2.7 There was no error stack, just that line in the log. I wiped the database (deleted all the files in the lib dir) and restarted my data load, and am consistently running into the

Re: sstable size change

Can you elaborate on what you mean by "let it take its own course organically"? Will Cassandra force any newly compacted files to my new setting as compactions are naturally triggered? From: sankalp kohli mailto:kohlisank...@gmail.com>> Reply-To: "user@cassandra.apache.org

Re: How to avoid inter-dc read requests

I simply monitor the load avg of the nodes using opscenter. I started with idle nodes (by idle I mean load avg of all nodes < 1.0), then started to run a lot of key slice read requests on *"analytic" DC *with CL local quorum (I also made sure that the client worked with only with analytic DC), afte

Re: cassandra 1.2.6 -> Start key's token sorts after end token

Out of curiosity, what version of hadoop are you using with cassandra? I think we are trying 0.20.2 if I remember(I have to ask my guy working on it to be sure). I do remember him saying the cassandra maven dependency was odd in that it is in the older version and not a newer hadoop version.

About column family

Hi all: i have two questions to ask: 1,how many column families can be created in a cluster?is there a limit to the number of it? 2,it spents 2-5 seconds to create a new cf while the cluster contains about 1 cfs(if the cluster is empty,it spents about 0.5s).is it normal?how to improve the ef

Re: memtable overhead

An empty memtable would not take up much space, a few KB I would assume. However they are considered in the calculations that control how frequently to flush to disk. The more CF's, even if they do not have data, the more frequently you will flush to disk. Cheers - Aaron Morto

Re: Cassandra Out of Memory on startup while reading cache

As a work around remove the key / row caches before startup. Cheers - Aaron Morton Cassandra Consultant New Zealand @aaronmorton http://www.thelastpickle.com On 23/07/2013, at 6:44 AM, Janne Jalkanen wrote: > > Sounds like this: https://issues.apache.org/jira/browse/CASSANDR

Re: CL1 and CLQ with 5 nodes cluster and 3 alives node

>> I really don't think I have more than 500 million rows ... any smart way to >> count rows number inside the ks? use the output from nodetool cfstats, it has a row count and bloom filter size for each CF. You may also want to upgrade to 1.1 to get global cache management, that can make things

Re: Socket buffer size

> Has anyone tried configuring the (internode_send_buff_size_in_bytes) > parameter? > > Here is the Traceback (most recent call last): Are you setting this on the client or the server ? It's a server side setting from the cassandra.yaml file. Cheers - Aaron Morton Cassandra C

Re: OPP seems completely unsupported in Cassandra 1.2.5

> - I know that OPP is deprecated. Is it that OPP completely unsupported? Is > it stated in upgrade instructions or some where? Did we miss it? > Basically yes, OPP is not going to work in 1.2 because of the System tables. I don't think you'll find any upgrade instructions anywhere because to be h

Re: CPU Bound Writes

That's very old documentation, try using the current docs. Although the statement is syntactically correct, it will become CPU bound before becoming memory bound. That statement says nothing about the IO use. Cheers - Aaron Morton Cassandra Consultant New Zealand @aaronmorton

Re: Are Writes disk-bound rather than CPU-bound?

> “/Insert-heavy workloads will actually be CPU-bound in Cassandra before being > memory-bound/” What is the source for that ? > This is because everything is > *first *written to the commit log *on disk*. Any thoughts?? Pretty much. Cheers - Aaron Morton Cassandra Consultant N

Re: How to avoid inter-dc read requests

> All the read/write request are issued with CL local quorum, but still > there're a lot of inter-dc read request. > How are you measuring this ? Cheers - Aaron Morton Cassandra Consultant New Zealand @aaronmorton http://www.thelastpickle.com On 22/07/2013, at 8:41 AM, sankalp

Re: funnel analytics, how to query for reports etc.

For background on rollup analytics: Twitter Rainbird http://www.slideshare.net/kevinweil/rainbird-realtime-analytics-at-twitter-strata-2011 Acunu http://www.acunu.com/ Cheers - Aaron Morton Cassandra Consultant New Zealand @aaronmorton http://www.thelastpickle.com On 22/07/20

Re: Safely adding new nodes without losing data

I think you are correct. When the new node starts it randomly selects tokens, which result in a random set of token ranges being transferred from other nodes. For each pending range the existing token ranges in the cluster are searched to find one that contains the range we want to transfer.

Re: OPP seems completely unsupported in Cassandra 1.2.5

AFAIK, OPP is no longer supported and you should use ByteOrderedPartitioner (support of non-UTF characters too) instead : see http://www.datastax.com/docs/1.2/cluster_architecture/partitioners -- Cyril SCETBON On Jul 22, 2013, at 4:10 PM, Vara Kumar wrote: > We were using 0.7.6 version. And u