Re: Cassandra data model right definition

It's not that easy as I recall this email thread https://groups.google.com/forum/m/#!topic/nosql-databases/ZLdgwCT_PNU /Oskar > On 30 Sep 2016, at 18:40, Carlos Alonso wrote: > > Cassandra is a Wide Column Store http://db-engines.com/en/system/Cassandra > > Carlos Alonso

Re: Cassandra data model right definition

unsubscribe 3.10.2016 16:25 tarihinde Edward Capriolo yazdı: The phrase is defensible, but that is the root of the problem. Take for example a skateboard. "A skateboard is like a bike because it has wheels and you ride on it." That is true and defensively true. :) However with not much more

Re: Cassandra data model right definition

dra.apache.org> Sent: Monday, October 3, 2016 4:53:16 PM Subject: Re: Cassandra data model right definition My original point can be summed up as: Do not define cassandra in terms SMILES & METAPHORS. Such words include "like" and "close relative". For the specifics:

Re: Cassandra data model right definition

I did not ascribe blame. I only empathised with their predicament; I don't want to listen to either of us, either! On 3 October 2016 at 19:45, Edward Capriolo wrote: > You know what don't "go low" and suggest the recent un-subscriber on me. > > If your so eager to

Re: Cassandra data model right definition

You know what don't "go low" and suggest the recent un-subscriber on me. If your so eager to deal with my pull request please review this one: I would rather you review this pull request: https://issues.apache.org/jira/browse/CASSANDRA-10825 On Mon, Oct 3, 2016 at 1:04 PM, Benedict Elliott

Re: Cassandra data model right definition

Nobody is disputing that the docs can and should be improved to avoid this misreading. I've invited Ed to file a JIRA and/or pull request twice now. You are of course just as welcome to do this. Perhaps you will actually do it, so we can all move on with our lives! On 3 October 2016 at

Re: Cassandra data model right definition

"X-store" refers to how data is stored, in almost every case it refers to what logical constructs are grouped together physically on disk. It has nothing to do with whether a database is relational or not. Cassandra does, in fact meet the definition of row-store, however, I would like to

Re: Cassandra data model right definition

I've met clients that read the cassandra docs and then said in a big meeting "it's just like relational database, it has tables just like sqlserver/oracle." I'm not putting words in other people's mouth either, but I've heard that said enough times to want to puke. Does the docs claim cassandra

Re: Cassandra data model right definition

... and my response can be summed up as "you are not parsing English correctly." The word "like" does not mean what you think it means in this context. It does not mean "close relative." It is constrained to the similarities expressed, and no others. You don't seem to be reading any of my

Re: Cassandra data model right definition

It's a row store because its schemed (vs ad hoc documents), and data (rows) are stored together. What would you call the things you iterate over when you query a partition? Rows. That makes it a thing that stores "rows" of data, row store isn't some crazy stretch. On Mon, Oct 3, 2016 at 12:33 PM

Re: Cassandra data model right definition

Nobody is claiming Cassandra is a relational I'm not sure why that keeps coming up. On Mon, Oct 3, 2016 at 10:53 AM Edward Capriolo wrote: > My original point can be summed up as: > > Do not define cassandra in terms SMILES & METAPHORS. Such words include > "like" and

Re: Cassandra data model right definition

My original point can be summed up as: Do not define cassandra in terms SMILES & METAPHORS. Such words include "like" and "close relative". For the specifics: Any relational db could (and I'm sure one does!) allow for sparse fields as well. MySQL can be backed by rocksdb now, does that make it

Re: Cassandra data model right definition

A couple things I would like to note: 1. Cassandra does not determine how data is stored on disk, the compaction strategy does. One could, in theory, (and I believe some are trying) could create a column-store compaction strategy. There is a large effort in the database community overall to

Re: Cassandra data model right definition

Whether a storage engine requires schema isn't really critical for row oriented storage. How about CSV that doesn't have a header row? CSV is probably the most commonly used row oriented storage and tons of businesses still use it for B2B transactions. As you pointed out, some traditional RDBMS

Re: Cassandra data model right definition

Sorry Ed, but you're really stretching here. A table in Cassandra is structured by a schema with the data for each row stored together in each data file. Just because it uses log structured storage, sparse fields, and semi-flexible collections doesn't disqualify it from calling it a "row store"

Re: Cassandra data model right definition

I'll second Ed's comment. The documentation should be more careful when using phrases "like relational databases". When we look at the history of relational databases, people expect certain things like ACID transactions, primary/foriegn key constraints, query planners, joins and relational

Re: Cassandra data model right definition

https://github.com/apache/cassandra Row store means that like relational databases, Cassandra organizes data by rows and columns. The Cassandra Query Language (CQL) is a close relative of SQL. I generally do not know what to say about these high level

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: > >

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

Re: Cassandra data model right definition

-store, which is just utterly backwards as you mentioned. From: Benedict Elliott Smith <bened...@apache.org> Reply-To: <user@cassandra.apache.org> Date: Friday, September 30, 2016 at 5:12 PM To: <user@cassandra.apache.org> Subject: Re: Cassandra data model right definit

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: 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