Re: Cassandra data model right definition

I can iterate over JSON data stored in mongo and present it as a table with rows and columns. It does not make mongo a rowstore. On Fri, Sep 30, 2016 at 9:16 PM, Edward Capriolo wrote: > The problem with calling it a row store: > >

Row cache not working

Hi Everyone, My table looks like this - CREATE TABLE test.reads ( svc_pt_id bigint, meas_type_id bigint, flags bigint, read_time timestamp, value double, PRIMARY KEY ((svc_pt_id, meas_type_id)) ) WITH bloom_filter_fp_chance = 0.1 AND caching = {'keys': 'ALL',

Re: Cassandra data model right definition

The problem with calling it a row store: https://en.wikipedia.org/wiki/Row_(database) In the context of a relational database , a *row*—also called a record or tuple

Replacing a dead node in a live Cassandra Cluster

Hello Cassandra-users, I was running some tests today. My end goal was to learn more about replacing a dead node in a live Cassandra cluster with minimal disruption to the existing cluster and figure out a better and faster way of doing the same. I am running a package installation of the

Re: Cassandra data model right definition

I agree 100%, this misunderstanding really bothers me as well.  I like the term “Partitioned Row Store” even though I am guilty of using the legacy “Column-Family Store” from darker times.  Even databases like Scylla which is supposed to be an Apache Cassandra clone tout themselves as a

Re: Cassandra data model right definition

Absolutely. A "partitioned row store" is exactly what I would call it. As it happens, our README thinks the same, which is fantastic. I thought I'd take a look at the rest of our cohort, and didn't get far before disappointment. HBase literally calls itself a "*column-oriented* store" - which

Re: Cassandra data model right definition

+1000 to what Benedict says. I usually call it a "partitioned row store" which usually needs some extra explanation but is more accurate than "column family" or whatever other thrift era terminology people still use. On Fri, Sep 30, 2016 at 1:53 PM DuyHai Doan wrote: > I

Re: Cassandra data model right definition

Then: Physically: A data store which physically structured-log-merge of SSTables (see) https://cloud.google.com/bigtable/. Now: One of the change made in Apache Cassandra 3.0 is a relatively important refactor of the storage engine . I say

Re: Way to write to dc1 but keep data only in dc2

Thanks Edward. Looks like it's not possible what I really wanted (to use some kind of a quorum write ex). Note that the queue is ordered, but I need just so they eventually happen, but with more consistency than ANY (2 nodes or more). On Fri, Sep 30, 2016 at 12:25 AM, Edward Capriolo

[ANNOUNCE] Achilles 5.1.0

Hello C* users I'm happy to announce the release of Achilles 5.1.0, the first mapper which is Cassandra-version aware e.g. it only generates source code that corresponds to the features supported by your C* version. - C* 2.1: base version - C* 2.2: UDF, UDA, JSON syntax - C* 3.0: materialized

Re: Difference in token range count

Hi Eric, Thanks for the reply... RF=3 for all DCs... On Fri, Sep 30, 2016 at 9:57 PM, Eric Stevens wrote: > What is your replication factor in this DC? > > On Fri, Sep 30, 2016 at 8:08 AM techpyaasa . wrote: > >> Hi , >> >> We have c*-2.0.17 with 3

Re: Cassandra data model right definition

I used to present Cassandra as a NoSQL datastore with "distributed" table. This definition is closer to CQL and has some academic background (distributed hash table). On Fri, Sep 30, 2016 at 7:43 PM, Benedict Elliott Smith wrote: > Cassandra is not a "wide column store"

Re: Cassandra data model right definition

Cassandra is not a "wide column store" anymore. It has a schema. Only thrift users no longer think they have a schema (though they do), and thrift is being deprecated. I really wish everyone would kill the term "wide column store" with fire. It seems to have never meant anything beyond

Re: Cassandra data model right definition

Hi Mehdi, I can help clarify a few things. As Carlos said, Cassandra is a Wide Column Store. Theoretically a row can have 2 billion columns, but in practice it shouldn't have more than 100 million columns. Cassandra partitions data to certain nodes based on the partition key(s), but does

Re: Cassandra data model right definition

Cassandra is a Wide Column Store http://db-engines.com/en/system/Cassandra Carlos Alonso | Software Engineer | @calonso On 30 September 2016 at 18:24, Mehdi Bada wrote: > Hi all, > > I have a theoritical question: > - Is Apache

Cassandra data model right definition

Hi all, I have a theoritical question: - Is Apache Cassandra really a column store? Column store mean storing the data as column rather than as a rows. In fact C* store the data as row, and data is partionned with row key. Finally, for me, Cassandra is a row oriented schema less DBMS

Re: C* files getting stuck

Hello Amit - I can confirm that we also experienced this issue in 2.0.x and were not able to find a solution other than a restart. Since upgrading to 2.2.x the problem did disappear. Thanks, Paul Fife On Fri, Sep 30, 2016 at 6:48 AM, Amit Singh F wrote: > Hi All, >

Difference in token range count

Hi , We have c*-2.0.17 with 3 data centers . Each data center has 9 nodes. vnodes enabled in all nodes. When I ran -local repair(./nodetool -local repair keyspace_name1 columnfamily_1) on one of data center I saw following print "Starting repair command #3, repairing *2647 ranges* for keyspace

RE: C* files getting stuck

Hi All, Please check if anybody has faced below issue and if yes what best can be done to avoid this.? Thanks in advance. Regards Amit Singh From: Amit Singh F [mailto:amit.f.si...@ericsson.com] Sent: Wednesday, June 29, 2016 3:52 PM To:

Error while read after upgrade from 2.2.7 to 3.0.8

Hi, Since the upgrade from Cassandra version 2.2.7 to 3.0.8 We're getting following error almost every several minutes on every node. For node at 173.170.147.120 error in system.log would be: INFO [SharedPool-Worker-4] 2016-09-30 10:26:39,068 Message.java:605 - Unexpected exception during

High CPU usage by cqlsh when network is disconnected on client

Hi, We are using Cassandra 3.6 and I have been facing this issue for a while. When I connect to a cassandra cluster using cqlsh and disconnect the network keeping cqlsh on, I get really high cpu utilization on client by cqlsh python process. On network reconnect things return back to normal.