Re: Deleting a column vs setting it's value to empty

<< Setting to "" may cause you less headaches as you won't have to deal with tombstones >> You won't have to deal with tombstones manually, the Thrift API will take care of this. Deleting an empty column value will always be better; with one exception, when "empty" does actually mean something e

Re: Querying for rows without a particular column

One option might be to maintain an index containing the keys of the rows. The index would then have the same TTL as the row itself so when you iterate over the index columns you'll find exactly the same results. Although I'm not really sure whether this is the best option. Another might be to use

Re: Got fatal exception after upgrade to 1.0.7 from 1.0.6

Would you mind opening a ticket on https://issues.apache.org/jira/browse/CASSANDRA. -- Sylvain On Tue, Feb 14, 2012 at 12:51 AM, Roshan wrote: > Hi > > I got the below exception to the system.log after upgrade to 1.0.7 from > 1.0.6 version. I am using the same configuration files which I used in

Re: Querying for rows without a particular column

This is an interesting usecase. If you implement it correctly then you may end up getting all the rows in your cluster for certain bad queries :)...so be careful. I would ask why do you want to know such rows and what will you do with them? -Naren On Mon, Feb 13, 2012 at 12:16 PM, Asankha C. Pe

stalled bootstrap

Hi, I'm running the DataSatx 1.0.7 AMI in ec2. I started with two nodes and have just added a third node on the way to expanding to a four node cluster. The bootstrapping was going along ok for a while, but has stalled. In /var/log/cassandra/system.log I am seeing this repeated continuously (tmp

Re: Querying all keys in a column family

Hey Martin, Have you tried CQL query: "SELECT FIRST 0 * FROM cfName" ? Cheers, Alex On Mon, Feb 13, 2012 at 11:00 PM, Martin Arrowsmith < arrowsmith.mar...@gmail.com> wrote: > Hi Experts, > > My program is such that it queries all keys on Cassandra. I want to do > this as quick as possible, in o

Re: active/pending queue lengths

And the output from tpstats is ? A - Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 14/02/2012, at 12:43 PM, Franc Carter wrote: > On Tue, Feb 14, 2012 at 6:06 AM, aaron morton wrote: > What CL are you reading at ? > > Quorum > > > Write ops g

Re: Querying all keys in a column family

If you want to process 1 million rows use Hadoop with Hive or Pig. If you use Hadoop you are not doing things in real time. You may need to rephrase the problem. Cheers - Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 14/02/2012, at 11:00 AM, Ma

Re: Querying for rows without a particular column

I would try to come up with a different model. Expired columns are essentially deleted columns. Can you create a manual secondary index that uses the time the column will have expired at. e.g. row: column: When you write the row with the expiry time also write a column here that says this

Re: active/pending queue lengths

On Tue, Feb 14, 2012 at 8:01 PM, aaron morton wrote: > And the output from tpstats is ? > I can't reproduce it at the moment ;-( nodetool is throwing 'Failed to retrieve RMIServer stub:' - which I'm guessing/hoping is related to the stalled bootstrap. > > A > > - > Aaron Mo

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Re: [RELEASE] Apache Cassandra 0.8.10 released

No more RPMs from DataStax? http://rpm.datastax.com/community/x86_64/ On Mon Feb 13 10:40:13 2012, Sylvain Lebresne wrote: The Cassandra team is pleased to announce the release of Apache Cassandra version 0.8.10. Cassandra is a highly scalable second-generation distributed database, bringing t

Key cache hit rate issue

Hi, I'm using Cassandra 1.0.7 and I've set the keys_cached to about 80% (using the numerical values). This is visible in cfstats too. But I'm getting less than 20% (or sometimes even 0%) key cache hit rate. Well, the data access pattern is not the issue here as I know they are retrieving the same

Re: [RELEASE] Apache Cassandra 0.8.10 released

On 02/14/2012 09:23 AM, Rustam Aliyev wrote: > No more RPMs from DataStax? > > http://rpm.datastax.com/community/x86_64/ They'll show up under /noarch/, if you are looking manually. The cassandra debs and rpms will be built/tested/uploaded to the DataStax repositories as soon as possible, whenev

Re: [RELEASE] Apache Cassandra 0.8.10 released

FYI: we use redminerpm ant tasks to build rpms automatically from our builds. http://redline-rpm.org/ On Tue, Feb 14, 2012 at 9:23 AM, Michael Shuler wrote: > On 02/14/2012 09:23 AM, Rustam Aliyev wrote: > > No more RPMs from DataStax? > > > > http://rpm.datastax.com/community/x86_64/ > > They'll

Re: [RELEASE] Apache Cassandra 0.8.10 released

On 02/14/2012 11:40 AM, Paul Loy wrote: > FYI: we use redminerpm ant tasks to build rpms automatically from our > builds. http://redline-rpm.org/ Thanks for the info, I appreciate it. This looks very interesting. -- Kind regards, Michael

unsubscribe

Re: unsubscribe

http://wiki.apache.org/cassandra/FAQ#unsubscribe On Tue, Feb 14, 2012 at 1:37 PM, Al wrote: >

deleting rows and tombstones

my design calls for deleting a row (by key, not individual columns) and re-inserting it a lot and I'm concerned about tombstone build up slowing down reads. I know if I delete a lot of individual columns the tombstones will build up and slow down reads until they are cleaned up, but not sure if

Re: deleting rows and tombstones

Are you planning to insert rows with keys that existed before? If that's true, there will be no tombstones (as far as I understand Cassandra). It that's not, then you will get tombstones that might slow down the reads because they have to be skipped until the next compaction. 2012/2/14 Todd Burr

timed-out retrieving a giant row.

Hi all, I'm using the Hector client 0.8, trying to retrieve a list of IDs from a gaint row. each ID is a columnName in the row It works ok when there's not many IDs, but SliceQuery starts to time-out after the row becomes big. Is this approach the correct way to store a list of IDs? are there som

Re: timed-out retrieving a giant row.

I'm familiar to this in PHPCassa, but with Hector it would be something like this: Query you CF with a range.setStart(lastColName) and range.setFinish(StringUtils.byte("") where the " lastColName " is the name of the column from the previous read. You can continue this until you run out of result

Re: timed-out retrieving a giant row.

Of course you should set your limit to 100 or something like that, not Integer.MAX_VALUE ;-) 2012/2/14 R. Verlangen > I'm familiar to this in PHPCassa, but with Hector it would be something > like this: > > Query you CF with a range.setStart(lastColName) and > range.setFinish(StringUtils.byte(""

Re: deleting rows and tombstones

Hi Todd, Our systems do a lot of deletions and it does cause problems. Your best bet is to bring GCSeconds low and run repair religiously. The issue you can run into though is repair overloading your servers when your data load gets high, repair falling over and related problems. IMHO the need t

Re: deleting rows and tombstones

yes, I will be re-inserting using the same keys. the reason I believe the tombstone behavior may be different is that (if I remember correctly) there is a "marked for delete" flag on the row in the SSTABLE. this could provide better performance than marking individual columns as deleted and ha

Re: deleting rows and tombstones

do you find that repair is still as necessary now since hinted handoffs are stored anytime a node does not ACK successfully? From: Dominic Williams mailto:dwilli...@fightmymonster.com>> Reply-To: "user@cassandra.apache.org" mailto:user@cassandra.apache.org>> Da

nodetool removetoken

I teminated (ec2 destruction) a node that I was wedged during bootstrap. However when I try to removetoken I get 'Token not found'. It looks a bit like this issue ? https://issues.apache.org/jira/browse/CASSANDRA-3737 nodetool -h 127.0.0.1 ring gives this Address DC Rack

Re: nodetool removetoken

Before 1.0.8, use https://issues.apache.org/jira/browse/CASSANDRA-3337 to remove it. On Tue, Feb 14, 2012 at 3:44 PM, Franc Carter wrote: > > I teminated (ec2 destruction) a node that I was wedged during bootstrap. > However when I try to removetoken I get 'Token not found'. > > It looks a bit li

Re: nodetool removetoken

On Wed, Feb 15, 2012 at 8:49 AM, Brandon Williams wrote: > Before 1.0.8, use https://issues.apache.org/jira/browse/CASSANDRA-3337 > to remove it. > I'm missing something ;-( I don't see a solution in this link . . cheers > > On Tue, Feb 14, 2012 at 3:44 PM, Franc Carter > wrote: > > > > I t

Re: nodetool removetoken

On Tue, Feb 14, 2012 at 2:02 PM, Franc Carter wrote: > On Wed, Feb 15, 2012 at 8:49 AM, Brandon Williams wrote: > >> Before 1.0.8, use https://issues.apache.org/jira/browse/CASSANDRA-3337 >> to remove it. >> > > I'm missing something ;-( I don't see a solution in this link . . > The solution is a

Re: nodetool removetoken

On Wed, Feb 15, 2012 at 9:25 AM, Rob Coli wrote: > On Tue, Feb 14, 2012 at 2:02 PM, Franc Carter > wrote: > >> On Wed, Feb 15, 2012 at 8:49 AM, Brandon Williams wrote: >> >>> Before 1.0.8, use https://issues.apache.org/jira/browse/CASSANDRA-3337 >>> to remove it. >>> >> >> I'm missing something

Re: deleting rows and tombstones

Hi that's a good question. Maybe we are hanging on to lessons we shouldn't need but... Currently even on 1.07 we still get significant deleted data popping when repair hasn't run. The irony is that it is usually cluster disruption caused by repair-initiated compaction storms that seem to be the d

Re: Got fatal exception after upgrade to 1.0.7 from 1.0.6

Issue seems related to https://issues.apache.org/jira/browse/CASSANDRA-3677 or exactly same. I am happy to create another if this is different. Please confirm. -- View this message in context: http://cassandra-user-incubator-apache-org.3065146.n2.nabble.com/Got-fatal-exception-after-upgrade-to-

Re: deleting rows and tombstones

I +1'd CASSANDRA-3620 From: Dominic Williams mailto:dwilli...@fightmymonster.com>> Reply-To: "user@cassandra.apache.org" mailto:user@cassandra.apache.org>> Date: Tue, 14 Feb 2012 14:30:36 -0800 To: "user@cassandra.apache.org" m

Re: timed-out retrieving a giant row.

Thanks Robin! :) On Tue, Feb 14, 2012 at 12:23 PM, R. Verlangen wrote: > Of course you should set your limit to 100 or something like that, not > Integer.MAX_VALUE ;-) > > 2012/2/14 R. Verlangen > > I'm familiar to this in PHPCassa, but with Hector it would be something >> like this: >> >> Quer

Re: timed-out retrieving a giant row.

lookup ColumnSliceIterator in hector. this does what you want a lot easier than managing the "paging" From: Yuhan Zhang mailto:yzh...@onescreen.com>> Reply-To: "user@cassandra.apache.org" mailto:user@cassandra.apache.org>> Date: Tue, 14 Feb 2012 14:46:08 -0800

Re: stalled bootstrap

The assertion looks like a bug. Can you run it with DEBUG logging ? Do you have compression enabled ? Can you please submit a ticket here https://issues.apache.org/jira/browse/CASSANDRA with the extra info and update the email thread. I *think* that the node this is happening on is failing

Re: Key cache hit rate issue

Out of interest what does cfstats say about the bloom filter stats ? A high false positive could lead to a low key cache hit rate. > Also, is there a way to warm start the key cache, meaning pre-load the amount > of keys I set as keys_cached? See key_cache_save_period when creating the CF. Che

Re: Key cache hit rate issue

Its in the order of 261 to 8000 and the ratio is 0.00. But i guess 8000 is bit high. Is there a way to fix/improve it? Thanks, Eran Chinthaka Withana On Tue, Feb 14, 2012 at 3:42 PM, aaron morton wrote: > Out of interest what does cfstats say about the bloom filter stats ? A > high false positi