Resource: A great tutorial for Hadoop on local windows and Azure.

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Here’s the resource: http://gettingstarted.hadooponazure.com/gettingStarted.html > “HDInsight Jumpstart”

The Tutorial will teach you how to analyze log files using Hadoop Tools like MapReduce, Hive, SQooP – check it out! It works with both HDInsight for local windows as well as Hadoop on Azure:

HDInsight hadoop on windows starting guide tutorial

Conclusion:

I hope this resource helps you get started on building an end-to-end solution with Hadoop on Windows/Azure.

Quick Post: Uploading Local Data to Hadoop file system using Hadoop Command Line

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This is a Quick Post, Just want to share a command to upload local data to HDFS using Hadoop Command Line.

The command looks like:

> hadoop fs -copyFromLocal input.txt input/SqrtJob/input.txt

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inner workings of HDFS and MapReduce in a nutshell:

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HDFS and MapReduce inner workings in a nutshell.

HDFS MapReduce inner workings

Click on the image to view larger sized image

 

How to load some data to Hadoop on Windows to get started?

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In this post, I want to point out that HDInsight (Hadoop on Windows) comes with a sample datasets (log files) that you can load using the command:

1. Hadoop command Line > Navigate to c:HadoopGettingStarted

2. Execute the following command:

powershell -ExecutionPolicy unrestricted –F importdata.ps1 w3c

import data to hadoop on windows file system

After you have successfully executed the command, you can sample files in /w3c/input folder:

w3c log files iis hadoop on windows

Conclusion: In this post, we saw how to load some data to Hadoop on Windows file system to get started. Your comments are very welcome.

Official Resource: http://gettingstarted.hadooponazure.com/loadingData.html

Hadoop on Windows: How to Browse the Hadoop Filesystem?

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This Blog post applies to Microsoft® HDInsight Preview for a windows machine. In this Blog Post, we’ll see how you can browse the HDFS (Hadoop Filesystem)?

1. I am assuming Hadoop Services are working without issues on your machine.

2. Now, Can you see the Hadoop Name Node Status Icon on your desktop? Yes? Great! Open it (via Browser)

3. Here’s what you’ll see:

Hadoop File System Browse

4. Can you see the “Browse the filesystem” link? click on it. You’ll see:

hadoop file system name node status windows

5. I’ve used the /user/data lately, so Let me browse to see what’s inside this directory:

user data hadoop sqoop hive mapreduce

6. You can also type in the location in the check box that says Goto

7. If you’re on command line, you can do so via the command:

hadoop fs -ls /

hadoop command line list all files system

And if you want to browse files inside a particular directory:

hadoop command line sqoop mapreduce hdfs file system

Official Resource:

HDFS File System Shell Guide

Conclusion

In this post, we saw how to browse Hadoop File system via Hadoop Command Line & Hadoop Name Node Status

Related Articles:

Visualizing MapReduce Algorithm with an Example: Finding Max Temperature

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Problem Statement: Find Maximum Temperature for a city from the Input data.

Step 1) Input Files:

File 1:

New-york, 25

Seattle, 21

New-york, 28

Dallas, 35

File 2:

New-york, 20

Seattle, 21

Seattle, 22

Dallas, 23

File 3:

New-york, 31

Seattle, 33

Dallas, 30

Dallas, 19

Step 2: Map Function

Let’s say Map1, Map2 & Map3 run on File1, File2 & File3 in parallel, Here is their output:

(Note how it outputs the “Key – Value” pair. The key would be used by the reduce function later to do a “group by“)

Map 1:

Seattle, 21

New-york, 28

Dallas, 35

Map 2:

New-york, 20

Seattle, 22

Dallas, 23

Map 3:

New-york, 31

Seattle, 33

Dallas, 30

Step 3: Reduce Function

Reduce Function takes the input from Map1, Map2 & Map3, to give an output:

New-york, 31

Seattle, 33

Dallas, 35

Conclusion:

In this post, we visualized MapReduce Programming Model with an example: Finding Max Temp. for a city.  And as you can imagine you can extend this post, to visualize:

1) Find Minimum Temperature for a city.

2) In this post, the key was City, But you could substitute it by other relevant real world entity to solve similar looking problems.

I hope this helps.

Related Articles:

Visualizing MapReduce Algorithm with WordCount Example

Microsoft® HDInsight Preview for Windows: How to use Sqoop to load data into HDFS from SQL Server?

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In this post, we’ll see how to use Sqoop to load data into HDFS from SQL Server?

With that, here are the steps:

1. You have the Microsoft® HDInsight Preview for Windows Installed on your machine. Here’s a tutorial: Installing HDInsight (Microsoft’s Hadoop) on windows 7

2. Make sure that the Cluster is up & running! To check this, I click on the “Microsoft HDInsight Dashboard” or open http://localhost:8085/ on my machine

Did you get any “wait for cluster to start..” message? No? Great! Hopefully, all your services are working perfectly and you are good to go now!

3. Before we begin, decide on three things:

3a: Username and Password that Sqoop would use to login to the SQL Server database. If you create a new username and pasword, test it via SSMS before you proceed.

3b. select the table that you want to load into HDFS

In my case, it’s this table:

sql table to be loaded into hadoop hdfs from sql server3c: The target directory in HDFS. in my case I want it to be /user/data/sqoopstudent1

You can create by command: hadoop fs -mkdir /user/data/sqoopstudent1

[to learn about how to create directory, read: How to create a directory in Hadoop File System? ]

4. Now Let’s start the Hadoop Command Line (can you see the Icon on the Desktop? Yes? Great! Open that!)

5. Navigate to: c:Hadoopsqoop-1.4.2bin>

*This path may change in future, but navigate to the bin folder under the SQOOP_HOME.

6. Run dir command to see various files under this directory.

sqoop list files under the HOMe directory import export

Also you can run sqoop help for more information on the command that we are about to run.

sqoop list of commands help

7. Now here’s the command to Load data from SQL Server to HDFS:

c:Hadoopsqoop-1.4.2bin>sqoop import –connect “jdbc:sqlserver://localhost;dat
abase=UniversityDB;username=sqoop;password=**********” –table student –tar
get-dir /user/data/sqoopstudent1 -m 1

sqoop command to load data from sql server to hadoop file system

8. After successfully running the above command, let’s browse the file in HDFS!

sqoop see the content of the file

That’s about it for this post!

Thanks

Thanks Aviad Ezra who answered my question on this MSDN thread: An error while trying to use Sqoop on HDInsight to import data from SQL server to HDFS

Conclusion:

In this post, we saw how to load data into Hadoop from SQL Server using Sqoop (SQL Hadoop)

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