Hadoop Tutorial | Spark Kafka Nosql and BigData tools for DWH

            For Hadoop Interview Question See: Hadoop Interview Questions and Answers by rohit kapa from kapa rohit

                            Sqoop Installation: Sqoop is usefull for import/export sql or rdbms data files or table in hadoop HDFS or in Nosql. Download Sqoop 1.4.2 $ wget http://www.eu.apache.org/dist/sqoop/1.4.2/sqoop- 1.4.2.bin__hadoop-1.0.0.tar.gz Extract Sqoop 1.4.2 tarball, $ tar -zxvf sqoop-1.4.2.bin__hadoop-1.0.0.tar.gz Update the hadooprc.sh with export SQOOP_HOME $ cat hadooprc.sh export SQOOP_HOME=/data/sqoop-1.4.2 export JAVA_HOME=/usr/java/jdk1.7.0_05 export HADOOP_HOME=/data/hadoop-1.0.1 export HBASE_HOME=/data/ahbase-0.94.3 export PATH=$PIG_HOME/bin:$SQOOP_HOME/bin:$HIVE_HOME/bin:$JAVA_HOME/bin:$HA DOOP_HOME/bin:$PATH:$HBASE_HOME/bin export CLASSPATH=$JAVA_HOME:/data/hadoop-1.0.1/hadoop-core- 1.0.1.jar:$PIG_HOME/pig-0.10.0.jar Download the Mysql connector jar from, http://dev.mysql.com/downloads/connector/j/ extract ...

                                     Installation of PIG: 1. untar file tar -zxvf filename 2. go inside and export JAVA_HOME, HADOOP_HOME export JAVA_HOME=/home/user/jdk1.7-45 export HADOOP_HOME=/home/user/hadoop-1.2.1 3. start pig bin/pig 4. run commands on grunt prompt. grunt> a = load '/first' as (id:int,name:chararray,city:chararray); grunt> b = filter a by city == 'chennai'; grunt> c = foreach b generate name; grunt> dump c; grunt> store c into '/output'; grunt> b = foreach a generate id+1000; grunt> dump b; grunt> fs -copyFromLocal first / grunt> a = load '/first' as (id:int,name:chararray,city:chararray); grunt> b = foreach a generate city; grunt> dump b; grunt> ab = load '/infile.txt' using PigStorage(' ') as (first:chararray, last:charar...

                               Hbase Vs Cassandra: Historically, both HBase and Cassandra have a lot in common. HBase was created in 2007 at Powerset (later acquired by Microsoft) and was initially part of Hadoop and then became a Top-Level-Project. Cassandra originated at Facebook in 2007, was open sourced and then incubated at Apache, and is nowadays also a Top-Level-Project. Both HBase and Cassandra are wide-column key-value datastores that excel at ingesting and serving huge volumes of data while being horizontally scalable, robust and providing elasticity. There are philosophical differences in the architectures: Cassandra borrows many design elements from Amazon's DynamoDB system, has an eventual consistency model and is write-optimized while HBase is a Google BigTable clone with read-optimization and strong consistency. An i...

         Hbase Program to work On IDE like Eclipse: import java.io.IOException; import java.util.ArrayList; import java.util.List; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.hbase.HBaseConfiguration; import org.apache.hadoop.hbase.HColumnDescriptor; import org.apache.hadoop.hbase.HTableDescriptor; import org.apache.hadoop.hbase.KeyValue; import org.apache.hadoop.hbase.MasterNotRunningException; import org.apache.hadoop.hbase.ZooKeeperConnectionException; import org.apache.hadoop.hbase.client.Delete; import org.apache.hadoop.hbase.client.Get; import org.apache.hadoop.hbase.client.HBaseAdmin; import org.apache.hadoop.hbase.client.HTable; import org.apache.hadoop.hbase.client.Result; import org.apache.hadoop.hbase.client.ResultScanner; import org.apache.hadoop.hbase.client.Scan; import org.apache.hadoop.hbase.client.Put; import org.apache.hadoop.hbase.util.Bytes; public class HbaseTest {  ...

                          Hadoop, Hive, Hbase, Zookeeper:   Hadoop is not a database Engine. Hadoop is a collection of File System (HDFS) and Java APIs to perform computation on HDFS. Furthermore Map Reduce is not technology, it is a Model to where you can work parallel on HDFS data. HBase is a NoSQL datastore that runs on top of your existing Hadoop cluster(HDFS). It provides you capabilities like random, real-time reads/writes, which HDFS being a FS lacks. Since it is a NoSQL datastore it doesn't follow SQL conventions and terminologies. HBase provides a good set of APIs(includes JAVA and Thrift). Along with this HBase also provides seamless integration with MapReduce framework. But, along with all these advantages of HBase you should keep this in mind that random read-write is quick but always has additional overhead. So think well before ye make any d...

                     Hive Installation: 1. untar file tar -zxvf filename 2. go inside and export JAVA_HOME, HADOOP_HOME export JAVA_HOME=/home/user/jdk1.7-45 export HADOOP_HOME=/home/user/hadoop-1.2.1 3. start hive bin/hive 4. show databses show tables

Hadoop Configuration with Eclipse IDE for development 1. Go inside user dir and if you installed eclipse as root cd /opt/eclipse/plugins/ 2. Put plugins cp hadoop-eclipse-plugin-1.0.4 /opt/eclipse/plugins/ 3. Start hadoop 4. Start eclipse(you may start from shell write eclipse and close shell) 5. Right click on mapreduce location beside consol in eclipse and click on new hadoop location. 6. On define hadoop location prompt fill    location name=111.111.1.111    map/reduce master    dfs master    host=111.111.1.111       port=50310        port 50311    click finish    ur hdfs is configured 7. In updation right click on dfs location tab and click refresh/reconnect. 8. file->new project-> Mapreduce Project->projectName-> (configure hadoop location where you installed it.) then write mapreduce/wordcount program.

WordCount Program in MapReduce  package org.dkrajput.mr; import java.io.IOException; import java.util.StringTokenizer; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.Path; import org.apache.hadoop.io.IntWritable; import org.apache.hadoop.io.Text; import org.apache.hadoop.mapreduce.Job; import org.apache.hadoop.mapreduce.Mapper; import org.apache.hadoop.mapreduce.Reducer; import org.apache.hadoop.mapreduce.lib.input.FileInputFormat; import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat; public class WordCount2 {   public static class TokenizerMapper        extends Mapper<Object, Text, Text, IntWritable>{     private final static IntWritable one = new IntWritable(1);     private Text word = new Text();     public void map(Object key, Text value, Context context                     ) throws IOException...

              Hadoop Installation: You can configure hadoop in any Operating System, but the main power of hadoop comes with linux. 1. configure on windows -  using cigwin             -  using virtual machine - install ubuntu. see below link. (http://hadoop.apache.org/docs/r2.3.0/hadoop-project-dist/hadoop-common/SingleNodeSetup.html) 2. configure on Linux machine. /home/Admin/ su - root password: root adduser dav passwd dav (now my user name and password both are set as dav) su - dav password: dav (now i am login with my user) pwd /home/dav/ step1: download hadoop - Use the latest stable release from Hadoop site and I used hadoop-1.2.1.tar.gz, it tarball file. step2: Install java jdk1.6 or jdk1.7 or just put it here as it is. step3: tar -zxvf hadoop-1.2.1.tar.gz (now it) mkdir hdfstmp (it will create hdfstmp dir here) go inside the ...

                    hadoop architecture Input Data -(Split) -(Record Reader) Mapper(tokenize in strings)-[a,1][a,1][b,1], [a,1][b,1] Combiner(combine similer)-[a,1,1][b,1], [a,1][b,1] Partitioning(partition on basis of similarity)[a,1,1], [b,1],  [a,1], [b,1] Shuffle and sort(shuffle phase sorts the resulting pairs from the combiner phase, after which, data goes to reducer)[a,1,1,1], [b,1,1] Reducer.[a,3], [b,2] for more info see this https://developer.yahoo.com/hadoop/tutorial/module4.html

          Index to learn BigData Hadoop Fremework Apache Hadoop is an open-source software framework for storage and large-scale processing of data-sets on clusters of commodity hardware. Hadoop is an Apache top-level project being built and used by a global community of contributors and users.It is licensed under the Apache License 2.0. The Apache Hadoop framework is composed of the following modules: Hadoop Common – contains libraries and utilities needed by other Hadoop modules Hadoop Distributed File System (HDFS) – a distributed file-system that stores data on commodity machines, providing very high aggregate bandwidth across the cluster. Hadoop YARN – a resource-management platform responsible for managing compute resources in clusters and using them for scheduling of users' applications. Hadoop MapReduce – a programming model for large scale data processing. Hadoop HDFS What is HDFS(Hadoop Distributed File Sys...

                                   What is Big Data   *  Every day, world create 2.5 quintillion bytes of data so much that 90% of the data in the world today has been created in the last two years alone. * Gartner defines Big Data as high volume, velocity and variety information assets that demand cost-effective, innovative forms of information processing for enhanced insight and decision making. *According to IBM, 80% of data captured today is unstructured, from sensors used to gather climate information, posts to social media sites, digital pictures and videos, purchase transaction records, and cell phone GPS signals, to name a few. All of this unstructured data is also Big Data. * Huge Competition in the Market:             ...