How do I list tables in HBase namespace?
HBase list_namespace_tables Command The list_namespace_tables command is used to list or display the tables available in given namespace. Below example display the tables available in ‘test’ namespace.
What is a namespace in HBase?
HBase automatically assigns a default namespace when you create a table and do not associate it with a namespace. A namespace that is used to contain HBase internal system tables. default. A namespace that contains all other tables when you do not assign a specific user-defined namespace.
How do I see all tables in HBase?
Listing Tables Using Java API
- You have a method called listTables() in the class HBaseAdmin to get the list of all the tables in HBase. This method returns an array of HTableDescriptor objects.
- You can get the length of the HTableDescriptor[] array using the length variable of the HTableDescriptor class.
Which HBase shell command do we use to modify HBase table configuration?
You can use the alter command to add, modify or delete column families or change table configuration options.
How do I create a multiple column family in HBase?
Syntax would be like this : create ‘
How many masters are possible in HBase?
How many masters are possible in hbase? In Hbase, a cluster consists of one Master and three or more Region Servers.
How do I find my HBase namespace?
HBase Limit Namespace Command If you want to view or display all the namespaces available in HBase, then you can use the list_namespace command in HBase.
What are the clients of HBase?
Chapter 6. HBase Clients
- The HBase shell.
- Kundera – the object mapper.
- The REST client.
- The Thrift client.
- The Hadoop ecosystem client.
How do I create a namespace in HBase?
The HBase shell has a set of straightforward commands for creating and dropping namespaces. You can assign a table to a namespace when you create the table. Creates a namespace with the name my_ns . Creates my_table with a column family identified as fam1 in the my_ns namespace.
How do I Desc a table in HBase?
Use describe command to describe the details and configuration of the HBase table. For example, version, compression, blocksize, replication e.t.c. The syntax to describe the table is as follows. Examples: When table created in a namespace, you need to qualify it on command.
What are the main key structures of HBase?
Ans. Row key and Column key are the fundamental key structures of HBase.
What is Phoenix HBase?
Apache Phoenix is an add-on for Apache HBase that provides a programmatic ANSI SQL interface. Phoenix provides: SQL and JDBC API support. Support for late-bound, schema-on-read. Access to data stored and produced in other components such as Apache Spark and Apache Hive.
What is list_namespace_table command in HBase?
HBase list_namespace_table command is being used to list or display all the tables created in a given namespace. Here the namespace name will the name for which you are looking to find the tables. HBase Drop Namespace Command. HBase drop_namespace command is being used to drop a namespace from HBase.
How do I create a new table in HBase?
Create Table inside HBase Namespace Once namespace is created, you can create the tables inside that namespace. Just like any other RDBMS schema, you have to append the namespace name with table name. By default tables will be created in HBase ‘default’ namespace.
What is HBase command in Hadoop?
HBase Command is an Open source Framework. It runs on Hadoop file distributed System (HDFS) use to store sparse data sets. The key components of HBase are Zookeeper, Region, HBase Master. Hbase consists of active HBase Master server and one Region Server.
How to sustain the capacity of the HBase cluster?
The capacity of the HBase cluster can be sustained by increasing the request handler thread count instantly. HBase shell and general commands give appropriate information about different data manipulation types, table management, and cluster replication commands. Various functions can be performed using these commands on tables present in HBase.