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Questions tagged [wide-column-store]

A wide column store is a type of key-value database. It uses tables, rows, and columns, but unlike a relational database, the names and format of the columns can vary from row to row in the same table.

Wide column store refers to databases like Apache Cassandra, Apache HBase, Apache Accumulo, Hypertable or Sqrrl. Databases good to store sparse table data.

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Why many refer to Cassandra as a Column oriented database?

Reading several papers and documents on internet, I found many contradictory information about the Cassandra data model. There are many which identify it as a column oriented database, other as a row-oriented and then who define it as a hybrid way…
cesare
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What exactly is a wide column store?

Googling for a definition either returns results for a column oriented DB or gives very vague definitions. My understanding is that wide column stores consist of column families which consist of rows and columns. Each row within said family is…
Moo
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Comparing Cassandra structure with Relational Databases

A few days ago I read about wide-column stored type of NoSQL and exclusively Apache-Cassandra. What I understand is that Cassandra consist of: A keyspace(like database in relational databases) and supporting many column families or tables (Same as…
Mohammad Sina Karvandi
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Is Cassandra a column oriented or columnar database

Columnar database should store group of columns together. But Cassandra stores data row-wise. SS Table will hold multiple rows of data mapped to their corresponding partition key. So I feel like Cassandra is a row wise data store like MySQL but has…
saktheesh
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Wide column vs column family vs columnar vs column oriented DB definition

There's a lot of confusion among these terms. I'd like to throw my understanding out and see if people agree. I have seen conflicting and wrong definitions all over the web. In my mind, wide column and column family DBs are essentially the same…
Kenneth
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Columnar/Column-oriented database vs wide-column/column family database

I got really confused about Cassandra recently because most online material even AWS and Google describe it as columnar database. But actually it is row-based, partitioned, column-family database. Now everything makes sense to me: Then are all…
Stan
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Wide data frame with 4 columns to long data frame with 3 columns

I have a data frame (sample below), as follows: df = structure(list(Stage1yBefore = c("3.1", "1", "4", "2", "NA"), Stage2yBefore = c("NA", "2", "3.2", "2", "NA"), ClinicalActivity1yBefore = c(TRUE, TRUE, TRUE, TRUE, FALSE),…
Omry Atia
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Key-Value vs Wide-Column DB

I want to know what is the difference between a persistent key-value DB and a wide-column DB. I understand in both DBs you retrieve a single value by a key, so what is the difference between the types of the values? Thanks!
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How to access Amazon Keyspaces via shell?

I tried writing cqlsh in the AWS shell, but it returned no output. I referred this tutorial output:- bash: cqlsh: command not found
Samar Pratap Singh
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On Cassandra how to enable LDAP authentication

I have a Cassandra cluster running on Ubuntu. I would like to enable authentication so that not everyone will have access to the Cassandra database and run queries. Enabling simple authentication is available at…
NNK
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wide vs long format when saving data in pandas hdf5

pandas data frame are in general represented in long ( a lot of rows) or wide (a lot of columns) format. I'm wondering which format is faster to read and occupies less memory when saved as hdf file (df.to_hdf). Is there a general rule or some…
Donbeo
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Is DynamoDB a wide-column store?

Sources indicate that DynamoDB is a key/value store, document store, and/or wide-column store: At the core, DynamoDB is a key/value store. If the value stored is a document, DynamoDB provides some support for working with the underlying document.…
rinogo
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Is it possible to simultaneously create many new variables using mutate(), across(), starts_with(), and case_when()?

I have a wide-format longitudinal dataset with a set of variables that indicate what state a participant lived in for each year of the study period. If no participant lived in a given state that year, there is no level for that state in the…
leigh92
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filter for key-value pair in cassandra wide rows

I am trying to model time series data with many sensors (> 50k) with cassandra. As I would like to do filtering on multiple sensors at the same time, I thought using the following (wide row) schema might be suitable: CREATE TABLE data( time…
Calardan
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Is it a correct pattern to build composite primary key using wide columns stores?

HBase and Cassandra are built as wide column stores, using the concepts of both rows and columns. A row is composed of a key similar to the concept of primary key in RDBMS and a value composed of several columns A representation can be the…
amirouche
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