Stack Overflow
Stack Overflow

Questions tagged [column-family]

A column family is a NoSQL object that contains columns of related data. It is a tuple (pair) that consists of a key-value pair, where the key is mapped to a value that is a set of columns. In analogy with relational databases, a column family is as a "table".

65 questions
1
vote
1 answer

Not enough bytes to read value of component using Composite Columns with Astyanax client

I am tyring to insert into Composite Column in Cassandra column family using Astyanax client. Below is my column family in Cassandra. create column family USER_DATA with key_validation_class = 'UTF8Type' and comparator =…
arsenal
  • 20,650
  • 79
  • 217
  • 317
1
vote
1 answer

Static Column Family in Cassandra vs Dynamic Column Family?

I have started working with Cassandra and I was going through Static column family and Dynamic column family and I am wondering when do we use static column family as compared to dynamic column family? In my use case, I will be having huge JSON…
AKIWEB
  • 16,538
  • 58
  • 164
  • 276
1
vote
1 answer

Cassandra. How to create column family using FluentCassandra API?

I'm trying to create column family with this code public void CreateAColumnFamily() { using (var db = new CassandraContext(keyspace:"Earth", server: Server)) { CassandraColumnFamily cf =…
user2686299
  • 417
  • 8
  • 22
0
votes
0 answers

Cassandra and column family and super column family

In Cassandra, you have to defined a table's schedule in terms of columns very much like relational DB. The difference is there is no table join and primary key can be composite key. But a column family definition says each row (column family) can…
Kenneth
  • 185
  • 1
  • 1
  • 8
0
votes
1 answer

Cassandra | Inserting data into two column families with the same row key

If I have 2 column families one for customer info and another for customer address info, how can I insert customer info and their address info to the two separate column families with the same row key(customer id) ?
JayaniH
  • 113
  • 1
  • 7
0
votes
1 answer

Does Hbase create a HFile for each column-family or columnFamily:Column?

I am trying to understand the Hbase architecture with respect to Logical data model vs Physical data storage. I am little confused about the HFile creation. If we have a column family with 2 columns, does Hbase create 2 HFiles or just one? Below is…
AnswerSeeker
  • 173
  • 2
  • 14
0
votes
1 answer

Cassandra data model - column-family

I checked some questions here like Understanding Cassandra Data Model and Column-family concept and data model, and some articles about Cassandra, but I'm still not clear what is it's data model. Cassandra follows a column-family data model, which…
croraf
  • 2,926
  • 2
  • 22
  • 37
0
votes
1 answer

Is Apache Cassandra not a good choice for aggregations?

I read that cassandra would not provide sufficient possibilities for aggregations like SUM or AVG. Actually I thought the column oriented model would be the most appropriate for these kind of operations. I read many articles, but I am just not…
TJack
  • 1
  • 1
0
votes
0 answers

If I write data into different column family of hbase concurrently, whether there is mutual influence

In my application, every thread is responsible for writing data into one column family, these threads may not start at the same time, but they may write data synchronously.
yi jiang
  • 206
  • 1
  • 11
0
votes
1 answer

Using rocksdb::Iterator and Column Family is not working

I have the following piece of code: rocksdb::DBWithTTL* db = ... rocksdb::WriteOptions writeOptions; rocksdb::ColumnFamilyHandle cfHandle = ... std::string keyPrefix = "prefix"; std::string key = keyPrefix + "_key"; std::string value =…
Mugen
  • 5,490
  • 3
  • 47
  • 97
0
votes
2 answers

Transfer data from one column family db to another column family

I'm new to Cassandra and Column family database world.I have a scenario where I need to move data from one Column family database such as Scylla Database to another Column family database Datastax Cassandra.Amount of data to be transferred will be…
Balaji Reddy
  • 4,901
  • 3
  • 30
  • 43
0
votes
1 answer

What are best practices for deleting/altering cassandra columns of collection data-type?

In our Cassandra table, every time we change data-types of "collection-type" columns it start causing issue. For example: For changing datatype from text to Map we do this: drop existing column wait for cassandra to assimilate this…
0biwan
  • 31
  • 1
  • 8
0
votes
2 answers

How can I skip HBase rows that are missing specific column family?

For example, a HBase table has columnFamilyA, columnFamilyB and columnFamilyC, for some rows, columnFamilyA does not have any column in it. I would like to scan the table and return only the rows that have at least one column in columnFamilyA. What…
user3483218
  • 11
  • 4
0
votes
0 answers

How to join multiple data sources in Cassandra

I'm working for the first time with Cassandra and I have some doubts. My data sources are csv files. I have three: flights, airplane and airport. I will put the structure of each csv file to contextualize my problem. Airport ID_airport | airport |…
Pedro Cunha
  • 301
  • 4
  • 15
0
votes
1 answer

How to get column family and qualifier of a HBase Table

I want to use the following: List cells = sourcePut.get(CfBytes, QualBytes); But it is returning me an empty list, since I am not specifying the correct column family and/or correct qualifier. For my source table, how to view all column…
Arijit
  • 330
  • 5
  • 13
1 2
3
4 5