You can create a table using the create command, here you must specify the table name and the Column Family name. The syntax to create a table in HBase shell is shown below.

create ‘<table name>’,’<column family>’

Example

Given below is a sample schema of a table named emp. It has two column families: “personal data” and “professional data”.

Row key	personal data	professional data

You can create this table in HBase shell as shown below.

hbase(main):002:0> create ’emp’, ‘personal data’, ‘professional data’

And it will give you the following output.

0 row(s) in 1.1300 seconds

=> Hbase::Table – emp

Verification

You can verify whether the table is created using the list command as shown below. Here you can observe the created emp table.

hbase(main):002:0> list

TABLE

emp

2 row(s) in 0.0340 seconds

Creating a Table Using java API

You can create a table in HBase using the createTable() method of HBaseAdmin class. This class belongs to the org.apache.hadoop.hbase.client package. Given below are the steps to create a table in HBase using java API.

Step1: Instantiate HBaseAdmin

This class requires the Configuration object as a parameter, therefore initially instantiate the Configuration class and pass this instance to HBaseAdmin.

Configuration conf = HBaseConfiguration.create();

HBaseAdmin admin = new HBaseAdmin(conf);

Step2: Create TableDescriptor

HTableDescriptor is a class that belongs to the org.apache.hadoop.hbase class. This class is like a container of table names and column families.

//creating table descriptor

HTableDescriptor table = new HTableDescriptor(toBytes(“Table name”));

//creating column family descriptor

HColumnDescriptor family = new HColumnDescriptor(toBytes(“column family”));

//adding coloumn family to HTable

table.addFamily(family);

Step 3: Execute through Admin

Using the createTable() method of HBaseAdmin class, you can execute the created table in Admin mode.

admin.createTable(table);

Given below is the complete program to create a table via admin.

import java.io.IOException;

import org.apache.hadoop.hbase.HBaseConfiguration;

import org.apache.hadoop.hbase.HColumnDescriptor;

import org.apache.hadoop.hbase.HTableDescriptor;

import org.apache.hadoop.hbase.client.HBaseAdmin;

import org.apache.hadoop.hbase.TableName;

import org.apache.hadoop.conf.Configuration;

public class CreateTable {

public static void main(String[] args) throws IOException {

// Instantiating configuration class

Configuration con = HBaseConfiguration.create();

// Instantiating HbaseAdmin class

HBaseAdmin admin = new HBaseAdmin(con);

// Instantiating table descriptor class

HTableDescriptor tableDescriptor = new

HTableDescriptor(TableName.valueOf(“emp”));

// Adding column families to table descriptor

tableDescriptor.addFamily(new HColumnDescriptor(“personal”));

tableDescriptor.addFamily(new HColumnDescriptor(“professional”));

// Execute the table through admin

admin.createTable(tableDescriptor);

System.out.println(” Table created “);

}

Compile and execute the above program as shown below.

$javac CreateTable.java

$java CreateTable

The following should be the output:

Table created

HBase – Listing Table

Listing a Table using HBase Shell

list is the command that is used to list all the tables in HBase. Given below is the syntax of the list command.

hbase(main):001:0 > list

When you type this command and execute in HBase prompt, it will display the list of all the tables in HBase as shown below.

hbase(main):001:0> list

TABLE

emp

Here you can observe a table named emp.

Listing Tables Using Java API

Follow the steps given below to get the list of tables from HBase using java API.

Step 1

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.

//creating a configuration object

Configuration conf = HBaseConfiguration.create();

//Creating HBaseAdmin object

HBaseAdmin admin = new HBaseAdmin(conf);

//Getting all the list of tables using HBaseAdmin object

HTableDescriptor[] tableDescriptor = admin.listTables();

Step 2

You can get the length of the HTableDescriptor[] array using the length variable of the HTableDescriptor class. Get the name of the tables from this object using getNameAsString() method. Run the ‘for’ loop using these and get the list of the tables in HBase.

Given below is the program to list all the tables in HBase using Java API.

import java.io.IOException;

import org.apache.hadoop.conf.Configuration;

import org.apache.hadoop.hbase.HBaseConfiguration;

import org.apache.hadoop.hbase.HTableDescriptor;

import org.apache.hadoop.hbase.MasterNotRunningException;

import org.apache.hadoop.hbase.client.HBaseAdmin;

public class ListTables {

public static void main(String args[])throws MasterNotRunningException, IOException{

// Instantiating a configuration class

Configuration conf = HBaseConfiguration.create();

// Instantiating HBaseAdmin class

HBaseAdmin admin = new HBaseAdmin(conf);

// Getting all the list of tables using HBaseAdmin object

HTableDescriptor[] tableDescriptor = admin.listTables();

// printing all the table names.

for (int i=0; i<tableDescriptor.length;i++ ){

System.out.println(tableDescriptor[i].getNameAsString());

}

Compile and execute the above program as shown below.

$javac ListTables.java

$java ListTables

The following should be the output:

User

emp

So, this brings us to the end of blog. This Tecklearn ‘How to create a Table in HBase shell’ helps you with commonly asked questions if you are looking out for a job in HBase and No-SQL Database Domain.

If you wish to learn HBase and build a career in HBase or No-SQL Database domain, then check out our interactive, Apache HBase Training, that comes with 24*7 support to guide you throughout your learning period. Please find the link for course details:

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What is NoSQL
NoSQL Vs RDBMS
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Data Modelling
HDFS vs. HBase
HBase Use Cases

HBase Architecture and Components

HBase Architecture
Components of HBase Cluster

HBase Installation

Prerequisites for HBase Installation
Installation Steps

Programming in HBase

Create an Eclipse Project for HBase
Simple Table Creation from Java in HBase
HBase API
HBase Shell
Primary operations and advanced operations

Integration of Hive with HBase

Create a table and insert data into it
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