Re: Modeling contact list, plain table or List

I have never used Materialized Views so maybe this suggestion is not possible, but in this case, wouldn't it make sense to define the materialized view as is_favourite IS TRUE instead of is_favourite IS NOT NULL? Carlos Alonso | Software Engineer | @calonso On 10 Ja

Re: Modeling contact list, plain table or List

The new Materialized View feature is just an automated way of creating and maintaining what people used to call a "query table", which is the traditional Cassandra data modeling technique for performing queries on on than the primary key for a table - you store the same columns in different tables

Re: Modeling contact list, plain table or List

In the current iteration of materialized view, it is still not possible to have WHERE clause other than IS NOT NULL so is_favourite IS TRUE won't work. Still there is a JIRA created to support this feature : https://issues.apache.org/jira/browse/CASSANDRA-10368 About cardinality of favorite vs no

Re: How do I upgrade from 2.0.16 to 2.0.17 in my case????

Thanks Michael, I'll try that then. I need to figure out how to do it with Ubuntu's upstart because I've not done it before. On 7 Jan 2016 4:25 pm, "Michael Shuler" wrote: > On 01/07/2016 07:52 AM, Vasileios Vlachos wrote: > > Hello, > > > > My problem is described CASSANDRA-10872 > >

sstableloader throughput

I have a need to stream data to new cluster using sstableloader. I spawned a machine with 32 cores assuming that sstableloader scaled with respect to cores. But it doesn't look like so. I am getting an average throughput of 18 MB/s which seems to be pretty low (I might be wrong). Is there any wa

Re: Using CCM with Opscenter and manual agent installation

> I believe the issue is just jmx_host needing to be set to 'localhost' Yes, that solved. Thanks! giampaolo 2016-01-08 5:17 GMT+01:00 Nick Bailey : > stomp_interface is the address to connect back to the central OpsCenter > daemon with, so 127.0.0.1 should be correct. I believe the issue is jus

Cassandra 1.2 & Compressed Data

We were running a contrived system test last week trying to measure the effect that compaction was having on our I/O and read performance. As a test, we set compaction throughput to 1MB/sec. As expected, we fell greatly behind and the number of SSTables grew. Unexpectedly, we went OOM. One of my

Re: sstableloader throughput

Make sure streaming throughput isn’t throttled on the destination cluster. Stream from more machines (divide sstables between a bunch of machines, run in parallel). On 1/11/16, 5:21 AM, "Noorul Islam K M" wrote: > >I have a need to stream data to new cluster using sstableloader. I >spa

Recommendations for an embedded Cassandra and Unit Tests

I'm looking to see what's recommended for an embedded version of Cassandra, just for unit testing. I'm looking at https://github.com/jsevellec/cassandra-unit/wiki but I wanted to see if there's was a better recommendation? -- -Richard L. Burton III @rburton

Re: Too many compactions, maybe keyspace system?

On Sat, Jan 9, 2016 at 8:23 AM, Shuo Chen wrote: > I don't know what exactly compaction logs is like in system.log. But I see > logs like this in system.log, I think maybe this is the compaction log > grep -i compact /path/to/system.log =Rob

Re: Recommendations for an embedded Cassandra and Unit Tests

Achilles 4.x does offer an embedded Cassandra server support with some utility classes like ScriptExecutor. It supports C* 2.2 currently : https://github.com/doanduyhai/Achilles/wiki/CQL-embedded-cassandra-server Le 11 janv. 2016 20:47, "Richard L. Burton III" a écrit : > I'm looking to see what

Re: Modeling contact list, plain table or List

The below table and materialized view will solve the SELECT requirements of my current application . The challenge now is when the user decides to DELETE one specific contact from his contact list. I could add the objectid to a composite partition key together with the userid. But that would mak

Re: Modeling contact list, plain table or List

That's the beauty of MV - Cassandra automatically updates the MVs when the base table changes, including deletions, which is why all of the PK columns from the base table needed to be in the MV PK. -- Jack Krupansky On Mon, Jan 11, 2016 at 3:41 PM, I PVP wrote: > The below table and materialize

Re: Modeling contact list, plain table or List

Well…the way it is now it is not possible to delete a specific contact row from the base table at all. Because a DELETE statement only works with PK in the WHERE clausule. Non PK columns cannot be in the DELETE WHERE clausule. https://docs.datastax.com/en/cql/3.3/cql/cql_reference/delete_r.htm

Re: Modeling contact list, plain table or List

You specify a userid and contactname to delete a single contact row in the base table. The MV is then updated accordingly. -- Jack Krupansky On Mon, Jan 11, 2016 at 4:20 PM, I PVP wrote: > Well…the way it is now it is not possible to delete a specific contact > row from the base table at all.

Re: Modeling contact list, plain table or List

In general I advise people avoid lists and use Maps or Sets instead. Using this data model, for instance, it's easy to remove a specific Address from a user: CREATE TYPE address ( street text, city text, zip_code int, ); CREATE TABLE user ( user_id int primary key, addresses map> )

Re: Recommendations for an embedded Cassandra and Unit Tests

What I'm noticing with these projects is that they don't handle CQL files properly. e.g., cassandra-unit dies when you have a string that contains ; inside of it. The parsing logic they use is very primitive in the sense they simple look for ; to denote the end of a statement. Is there any class i

Re: sstableloader throughput

On Mon, Jan 11, 2016 at 10:25 PM, Jeff Jirsa wrote: > > Make sure streaming throughput isn’t throttled on the destination cluster. > How do I do that? Is stream_throughput_outbound_megabits_per_sec the attribute in cassandra.yaml. I think we can set that on the fly using nodetool setstreamthrou

Re: what consistency level should I set when using IF NOT EXIST or UPDATE IF statements ?

Can anyone answer my questions ? I think the current datastax documents including python's one don't describe how we should set consistency with lightweight transactions precisely. Regards, Hiro On Fri, Jan 8, 2016 at 11:48 AM, Hiroyuki Yamada wrote: > Thanks Tyler. > > I've read the python doc

Re: Too many compactions, maybe keyspace system?

The lines you are looking for look like this : INFO [CompactionExecutor:48] 2016-01-12 09:07:59,995 CompactionTask.java (line 120) Compacting [SSTableReader(path='/usr/local/cassandra/data/system/sstable_activity/system-sstable_activity-jb-4959-Data.db'), SSTableReader(path='/usr/local/cassandra/d

Re: Too many compactions, maybe keyspace system?

I have a assumption that, lots of pending compaction tasks jam the memory and raise full gc. The full chokes the process and slows down compaction. And this causes more pending compaction tasks and more pressure on memory. Is there a method to list the concrete details of pending compaction tasks?

Re: Too many compactions, maybe keyspace system?

The attachment is result of grep -i GC /usr/local/cassandra/system.log > gc.log On Tue, Jan 12, 2016 at 1:12 PM, Shuo Chen wrote: > I have a assumption that, lots of pending compaction tasks jam the memory > and raise full gc. The full chokes the process and slows down compaction. > And this cau

Upgrade from 2.0.x to 2.2.x documentation missing

Hi, We are currently at Cassandra 2.0.14 in production and since it going to be EOL soon so we are planning to upgrade it to Cassandra 2.2.4 (http://cassandra.apache.org/download/) which is the currently production ready version. While doing some analysis we found that there is no such entry of

Re: Sorting & pagination in apache cassandra 2.1

What is the alternative if my cassandra version is prior to 3.0 (specifically) 2.1) and which is already in production.? Also as per the docs given at https://docs.datastax.com/en/datastax_enterprise/4.6/datastax_enterprise/srch/srchCapazty.html what does it mean by we need to do capacity planni

Re: Sorting & pagination in apache cassandra 2.1

1 more question, what does it mean by "cassandra inherently sorts data"? For eg: I have a table with schema CREATE TABLE users ( ... user_name varchar PRIMARY KEY, ... password varchar, ... gender varchar, ... session_token varchar,