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

Why do we need column families in Hbase?

What is the reason for having column families? Example: Scenario 1 : Table Row-Key ColumnFamily1 ColumnFamily2 ColumnFamily3 Scenario 2 : Table1 Row-Key Column1...ColumnN Table2 Row-Key Column1...ColumnN Table3 Row-Key Column1...ColumnN In…
user12318711
1
vote
1 answer

How to determine logical/physical reads and writes in cassandra?

I'am currently investigating read and writes operations on cassandra. I would like to know about the read and writes that cassandra performs on the memtable and sstable. What is the closest value of the cassandra metrics? All I found are latency…
Sebastian
  • 21
  • 4
1
vote
1 answer

Prefix search on a specific column in hbase not working in java

There is a column lets say Countries in hbase and I want to prefix on this column(this is not a row key) then I will use ColumnPrefixFilter and do something like this ColumnPrefixFilter columnPrefixFilter = new…
agrawal1084
  • 99
  • 2
  • 10
1
vote
1 answer

HBase Column family locality

there are HBase on five servers with one Table that contains one column Family and I should do some map tasks on it per each key and save the result. the main question is: to keep data locality which one is better: create new Column Family on the…
Hossein Vatani
  • 861
  • 8
  • 23
1
vote
0 answers

How do I choose between column-family and a document store database?

I'm working on a project, and I'm struggling to make a definitive decision on whether to use a column-family or a document store. My situation is as follows: The project I am working on is a hass.io application that will visualize certain data for…
Muggenhoofd2
  • 11
  • 1
1
vote
1 answer

Hbase multiple column families vs multiple tables

I'm developing a Hbase storage for data generated from different sources. Usually columns from the same source are more likely to be retrieved at the same time. The expected write/read ratio roughly range from 1/10 to 1/100 (depends on different…
twds
  • 283
  • 1
  • 2
  • 12
1
vote
2 answers

How to set the column family size for a Hbase table column family?

I am trying to import data from a CSV file into a HBase table. But I am running into the below shown exception during the import. Error: com.google.protobuf.InvalidProtocolBufferException: Protocol message was too large. May be malicious. Use…
AnOldSoul
  • 3,565
  • 7
  • 38
  • 90
1
vote
1 answer

How to get the range of tokens for only particular CF in cassandra by CQL?

I do want to repair a column family part by part using the command nodetool repair -st starting_token -et ending_token. As each row in column family have different range of token values,Is there any way to get the different token range possessed by…
arjun gowthaman
  • 11
  • 3
1
vote
1 answer

How can I create a column family without defining any column in apache phoenix?

According to the description on phoenix website: Following create table DDL will create two column faimiles A and B. CREATE TABLE TEST (MYKEY VARCHAR NOT NULL PRIMARY KEY, A.COL1 VARCHAR, A.COL2 VARCHAR, B.COL3 VARCHAR) But I need to create a…
Powpow
  • 130
  • 1
  • 7
1
vote
1 answer

Disadvantages of having more columnfamily in hbase?

I have read that in hbase, I should not have more than 2-3 column families in a table. I know that to fetch entries from each column family in a row, I need to do a separate scan, but still I don't understand what will be issue if I will have more…
Harsh Sharma
  • 9,634
  • 2
  • 13
  • 24
1
vote
0 answers

unconfigured columnfamily error on consecutive execute calls (CQL)

I'm using the cassandra python driver for datastax's distro. mah codez... from cassandra.io.libevreactor import LibevConnection from cassandra.cluster import Cluster cluster = Cluster(['some ip addr']) cluster.connection_class =…
Davis Dulin
  • 509
  • 4
  • 9
1
vote
2 answers

CQL3 Show Column Families

Can anybody tell how to get a list of column families under the current key space in Cassandra 2.0.4? Kindly note that am using cqlsh to query the server.
Babu James
  • 2,431
  • 4
  • 29
  • 48
1
vote
2 answers

delete row key from cassandra cli

i set my column family gcgraceseconds to 0; but stills rowkey is not deleted it remains in my column family create column family workInfo123 with column_type = 'Standard' and comparator = 'UTF8Type' and default_validation_class = 'UTF8Type' …
Govind Singh
  • 14,083
  • 12
  • 58
  • 94
1
vote
1 answer

what should I do if depth of my data increases in Cassandra?

How should I model my data for which the depth is more and it might increase in cassandra. Even if I add super column family, it would increase just one more level. (May be I am wrong, I am newbie to Cassandra). Assuming my data : { Key1 :…
Ayan
  • 485
  • 3
  • 9
  • 20
1
vote
2 answers

How to print configured columnfamilies in cassandra

I'm having some trouble getting a configuration script to match up with the columnfamily names I'm using. I feel like it would be a helpful debugging tool to be able to log all of the currently configured column families. Is this possible? I've been…
Slater Victoroff
  • 19,762
  • 18
  • 78
  • 135
1
2
3 4 5