HBase is free, open-source software from the Apache Foundation. It is a cross platform technology, so we can run it on Linux, Windows or OS/X machines and also can be hosted on Amazon Web Services and Microsoft Azure.
HBase is a NoSQL database which can run on a single machine, or cluster of servers. HBase provides data access in real-time. HBase tables can store billions of rows and millions of columns, unlike other big data technologies, which are batch-oriented. In HBase we have few key concepts like row key structure, column families, and regions.
To connection to HBase terminal:
1
> hbase shell
then it will change the prompt to hbase>;
General Commands:
To check the version of Hbase
1
hbase> version
To check the current hbase user
1
hbase> whoami
To show cluster status. Can be ‘summary’, ‘simple’, ‘detailed’, or ‘replication’. The default is ‘summary’.
1
2
3
4
5
6
7
hbase> status
hbase> status 'simple'
hbase> status 'summary'
hbase> status 'detailed'
hbase> status 'replication'
hbase> status 'replication', 'source'
hbase> status 'replication', 'sink'
Namespace Commands:
To create namespace in HBase
1
hbase> create_namespace 'namespace1'
To describe namespace in HBase
1
hbase> describe_namespace 'namespace1'
To list all namespaces in HBase
1
hbase> list_namespace
Optional regular expression parameter could be used to filter the output.
1
hbase> list_namespace 'name.*'
To drop the name space in HBase. To drop the name space, make sure that namespace is empty.
1
hbase> drop_namespace 'namespace1'
To list all tables that are members of the namespace in HBase