Aim: Install and run HBase and then use DDI and DML command.

Prerequisite:

1. Ubuntu installed

2. Installed java with environment variable set

3. Installed Hadoop with environment variable set( if not then install Hadoop)

Install and run HBase

To check the current version of Ubuntu type the below command

lsb_release -a

update and install squid

sudo apt update
sudo apt-get install squid

Download HBase from official site of the HBase

Apache HBase – Apache HBase Downloads

Extract the Hbase archive downloaded.

tar xvf hbase-<version>.tar.gz 
sudo mv hbase-<version>/ /

configure bashrc file to set environment variables

vim ~/.bashrc

paste this line with changing the path

export HBASE_HOME=/home/ashwin/hbase-<version>
export PATH=$PATH:$HBASE_HOME/bin

update the bashrc

source .bashrc

Open the file for editing.

sudo vim /usr/local/ashwin/conf/hbase-site.xml

Now add the following configurations between the <configuration> and </configuration> tags to look like below.

<configuration>
 <property>
 <name>hbase.rootdir</name>
 <value>file:/hadoop/HBase/HFiles</value>
 </property>

 <property>
 <name>hbase.zookeeper.property.dataDir</name>
 <value>/hadoop/zookeeper</value>
 </property>
</configuration>

Now start Hadoop by using

start-all.sh

Now start HBase by using

start-hbase.sh

the first task was done! 🙂 take a rest and come again for the next task

Use DDI and DML commands.

Let us see each DDL command in detail.

1. Create Table

Using create table command we can create a table by specifying the table name and column family.

Syntax

hbase(main):006:0> create ‘table name’,’column family’

Here we have created a table ‘employee’ with a two-column family (‘emp_address’,’emp_records’).

Command

hbase(main):006:0> create 'employee','emp_address','emp_records'

2. List

List command is used to display the tables which are present in HBase.

Syntax

hbase(main):006:0> list

Command

hbase(main):006:0> list

3. Describe

Describe command is used to display the table name with column families, associated filters, versions, and few more details.

Syntax

hbase(main):030:0> describe 'tablename'

Command

hbase(main):030:0> describe 'employee'

Let us see each DML command in detail.

1. Put

Put command is used to insert data in a table

To perform the Put operation, we will create a table with the name "employee" and insert data.

The structure of the table should look like below.

Syntax

hbase(main):015:0> put <'tablename'>,<'rowname'>,<'columnvalue'>,<'value'>

Command

hbase(main):015:0> create 'employee','emp_contact_data','emp_professional_data'
hbase(main):016:0> put 'employee','1','emp_contact_data:first_name','James'

2. Count

The count command is used to count the number of rows present in a table. Using the “Cache” option we can restrict the row which should be displayed. The default size of “Cache” is 10 rows.

Syntax

hbase(main):047:0> count <'tablename'>, CACHE =>1000

Command

hbase(main):047:0> count 'employee'

The below command is fetching 1000 rows at a time. In the output, the result is showing only five rows because there are only five rows present in table “employee”.

hbase(main):048:0> count 'employee',CACHE=>1000

3. Get

Get command is used to read data from a table.

Using the get command, we can read a single row of data at a time.

Syntax

hbase(main):051:0> get ’<table name>’,’row1’

Command

hbase(main):051:0> get 'employee', '1'

4. Scan

Scan command is used to view the complete data of a table “employee”.

Syntax

hbase(main):059:0> scan ‘<table name>’

Command

hbase(main):059:0> scan 'employee'

Done!🙂