Problem Statement: Find Maximum Temperature for a city from the Input data. Step 1) Input Files: File 1:
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:
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
I had never attended a conference of this scale before – so for me, it was a novel experience! An experience I will cherish (Until I get a chance to attend the next PASS!). And I am just amazed at kind of work the PASS board and volunteers must have put in to make this all happen. I remember a time when I was a lead organizer for a national level technical festival for just 500 attendees – and trust me when I say I had no chance to rest for 3-4 weeks straight. So when I see a conference that is 10x in size and 100x in reputation – All I can do is stare in amazement:
(Image Courtesy: dpshots )
So what did I do at SQLPASS?!
– Attended sessions to learn, relearn (and unlearn!)
( Image courtesy: http://www.lubbockstarprogram.com/?page_id=37 )
– Attended keynotes! Awesome announcements!! And on day three, I had the pleasure of seeing Dr. Dewitt live! – it was awesome!
– Went to parties ( I loved the
SolidQ party and the Game works party) Image courtesy: http://www.watton.org/clipart/party/party.shtml
– Met Amazing people who are passionate about same things I am!
– Met people who are part of the team that are responsible for developing/delivering products that I use daily => Met people with blue badges!
– Slept a little!
– Explored Seattle after PASS summit
– Volunteered as PASS ambassador
What was my job?! To guide people to find what they were looking for. So what I had to scout for confused faces – offer then help – point them to places – that’s about it.
– And tweeted a little during SQLPASS! #sqlpass rocks!
So yup – I enjoyed SQLPASS!
Cross Posted from:
http://beyondrelational.com/blogs/parasdoshi/archive/2011/10/17/sqlpass-2011-was-amazing.aspx 32.985909 -96.755436