Rajesh Sankaran Blog: June 2015

Tuesday, 30 June 2015

Microsoft Parallel Data Warehouse ( Microsoft PWD)

This article is shared from the link

http://www.pdwtutorial.com/2014/06/parallel-data-warehouse-introduction.html

Parallel Data Warehouse Introduction

The SQL Server 2008 R2 Parallel Data Warehouse (PDW) edition is its first product in the Massively Parallel Processor (MPP) data warehouse space.

PDW uniquely combines MPP software acquired from DATAllegro, parallel compute nodes, commodity servers, and disk storage.

PDW lets you scale out enterprise data warehouse solutions into the hundreds of terabytes and even petabytes of data for the most demanding customer scenarios. In addition, because the parallel compute nodes work concurrently, it often takes only seconds to get the results of queries run against tables containing trillions of rows. For many customers, the large data sets and the fast query response times against those data sets are game-changing opportunities for competitive advantage.

The simplest way to think of PDW [Parallel Data Warehouse Tutorial] is a layer of integrated software that logically forms an umbrella over the parallel compute nodes. Each compute node is a single physical server that runs its own instance of the SQL Server 2008 relational engine in a shared-nothing architecture. In other words, compute node 1 doesn't share CPU, memory, or storage with compute node 2.

The smallest PDW will take up two full racks of space in a data center, and you can add storage and compute capacity to PDW one data rack at a time. A data rack contains 8 to 10 compute servers from vendors such as Bull, Dell, HP, and IBM, and Fiber Channel storage arrays from vendors such as EMC, HP, and IBM. The sale of PDW includes preconfigured and pretested software and hardware that's tightly configured to achieve balanced throughput and I/O for very large databases. Microsoft and these hardware vendors provide full planning, implementation, and configuration support for PDW.

The collection of physical servers and disk storage arrays that make up the MPP data warehouse is often referred to as an appliance. Although the appliance is often thought of as a single box or single database server, a typical PDW appliance is comprised of dozens of physical servers and disk storage arrays all working together, often in parallel and under the orchestration of a single server called the control node. The control node accepts client query requests, then creates an MPP execution plan that can call upon one or more compute nodes to execute different parts of the query, often in parallel. The retrieved results are sent back to the client as a single result set.

This introduction taken from http://sqlmag.com/sql-server-2008/getting-started-parallel-data-warehouse

For your Reference

Friday, 19 June 2015

The 21 toughest interview questions you'll have to answer if you want to work at Yahoo

This article was taken from the TechGig...

The 21 toughest interview questions you'll have to answer if you want to work at Yahoo

"What gets you out of bed in the morning?" - Marketing associate candidate

"For mobile, which new application would you suggest Yahoo to develop? Why do you think Yahoo should develop it?" - Associate Product Manager candidate

"How would you handle correcting a mistake that your manager made?" - Software Engineer candidate

"Use this white board to explain how multiple regression works. " - Research Scientist candidate

"Given a string that contains a sentence, reverse each individual word in the sentence. For example, 'Hello to this world' becomes 'olleH ot siht dlrow'." - Software Engineer Intern candidate

"How would you distribute 1000 potatoes in 10 baskets?" - Software engineer candidate

"How does the internet work?" - Software Engineer candidate

"What is a company that is marketed poorly, and how would you market it differently? " - Associate Product Marketing Manager candidate

"You have a 10x10x10 rubix cube. You paint the outside. How many cubes have paint on them? " - Software Engineer candidate

"What is one thing you could teach the people in the other room?" - Service Engineering Operations candidate

"You're wearing a nametag. Tell me what you think about it." - Associate Product Manager candidate

"You have 10 jars, each filled with many marbles. Each marble weighs exactly 1.0 grams. One of the jars is a bad batch meaning each marble inside weighs 1.1 grams instead of 1.0 grams. You have a scale that will give you back a number of how much things weigh on it. Using only one measurement, determine how would you be able to find the bad batch." - Software Developer candidate

"Design the game Tic Tac Toe." - Software Engineer Intern candidate

"What will you do if the internet is not working?" - Software Engineer candidate

"Find all the possible ways to reach a floor in a building if you can only take 1, 2, or 5 steps at a time." - Software Developer candidate

"How will Google self-drive car change the public transit system if they are made available for general audience." - Product Manager candidate

"Who are key stakeholders for Yahoo paid search? How would you balance their interests as a product manager?" - Product Manager candidate

"How would you monetize YouTube?" - Product Manager candidate

"How would you design an elevator?" - Software Engineer candidate

"There are n gas stations positioned along a circular road. Each has a limited supply of gas. You can only drive clockwise around the road. You start with zero gas. Knowing how much gas you need to get from each gas station to the next and how much gas you can get at each station, design an algorithm to find the gas station you need to start at to get all the way around the circle." - Technical Architect candidate

"Estimate the volume of water on the Earth." - Senior Product Manager candidate

Tuesday, 9 June 2015

The 5 daily habits of the world’s most successful people

I would like to share an article I read on the LinkedIn .....

The 5 daily habits of the world’s most successful people

We all like to borrow from people we admire to get more productive. Highly successful Square founder Jack Dorsey strictly copied Steve Jobs, using much of Jobs’ onstage rhetoric when describing Square’s features and even insisting on being referred to as an ‘editor’ as soon as he heard that Jobs had adopted that title in some circles at Apple!

‘Editor’ may not suit you and your line of work, but there is a lot that you can glean from studying the working style of high performers.

The most successful people tend to share a striking number of similar habits that help them maximise their productivity and effectiveness.

Here are the top 5 things you can learn from the daily habits of the most successful people:

Wake up early

The early bird really does catch the worm! It’s no coincidence that many of the most successful people wake up early, many of the world’s top CEOs are well known for getting up as early as 430am.

Quite apart from giving you more time to get stuff done, getting up early sets a positive tone for the day – it’s satisfying to quell the inner voice that’s asking for ‘just 5 more minutes’ in bed.

Addicted to the snooze button? Joel Gascoigne, co-founder of Buffer, has a couple of great tips to help you create a morning routine that lasts (he’s up at 5am every day!)

Joel puts a lot of stock by:

1 - Getting to bed early every night to make sure you get enough sleep (he makes sure he gets around 7.5 hours a night)

2 - Waking up early on weekends – if he’s not up around 6am he finds it hard to keep up his routine

You may not need to be up quite so early every day, but establishing a routine to help you get a jump on the day and give yourself a little extra time should definitely help you become more efficient.

Exercise regularly

Quite apart from staying in shape, keeping your body active also goes along way to helping you feel more alert during the day.

Exercise increases the blood flow to your brain, keeping you sharp and helping you stay on top of everything

It’s also proven to keep you happy! Working up a sweat releases Serotonin, the neurotransmitter in the brain that sends messages to your body to stimulate mood and emotion.

It’s not just happiness though, studies have indicated that there are a range of other cognitive benefits:

- Improved concentration

- Sharper memory

- Faster learning

- Prolonged mental stamina

- Enhanced creativity

- Lower stress

The benefits are so clear that, no matter how busy you are, you should always try and find the time. Vogue editor-in-chief Anna Wintour commits to playing tennis for one hour every day – if she has time so do you!

Focus, don’t multitask

It might be tempting to try and maximise your daily productivity by doing as many things as possible, but sadly this only reduces efficiency and effectiveness (multitasking may even be bad for our brains!)

Instead of flitting between different tasks and trying to do everything at once, take the time to plan your day. Work out the 3-5 things that you need to accomplish over the course of the day and focus on them first. This will help you cut down on all the extra work that seems important but gets in the way.

I would advocate setting aside time the night before to think through the your major goals for the next day – I scribble mine down before I go to bed in my notepad. It’s the first thing I look at when I wake up and it helps me get my day off to a good start.

Many highly successful figures also point to meditation as a great tool to increase focus - Oprah Winfrey for example, finds time for two daily 20 minutes sessions of yoga and contemplation despite her packed schedule. She uses this time to focus and help our prioritize different tasks and projects.

Learn from mistakes

We all make mistakes, it’s inevitable. What separates the most successful people though, is their ability to constantly learn from their mistakes.

It’s easy to blame other people when things start to go wrong – throughout life (school, family and work) we’re taught to feel guilty about failure, so it’s no surprise that people are keen to pass the buck.

Smart people tend to admit their mistakes easily – it’s the first step towards understanding what went wrong, and it’s this understanding that helps you make positive changes to your life.

Take this quote from basketball legend Michael Jordan:

“I’ve missed more than 9000 shots in my career. I’ve lost almost 300 games. 26 times, I’ve been trusted to take the game winning shot and missed. I’ve failed over and over and over again in my life. And that is why I succeed.”

It’s ok not to be perfect, no one is. What’s really important though is that you’re constantly focused on learning how to get better.

Make personal investments

The world’s most successful people are always prepared to invest time and resources in their own personal development.

If you stripped someone like Bill Gates of his assets and dumped him on the street I’d be willing to bet he’d be ok – he’s constantly invested in himself and built up huge reserves of human capital, major companies would be falling over themselves to offer him a job.

Not everyone can hit the daunting heights that Gates has reached, but we can all work on ourselves and become invaluable to whatever business we’re involved with.

This can seem daunting initially, but there are a few good ways that you can kick off this process and start investing in yourself:

- Set weekly goals and review your progress.

We’re often too caught up in life that we fail to step back and look at the things that are most critical. Try setting 2-3 weekly goals and reviewing your progress every Sunday.

- Get a mentor (this may take time)

Make a list of the most experienced people in your industry, read everything they right and reach out on Twitter to start a relationship. Once you have a healthy amount of back and forth dialogue, ask for feedback on your career and your goals.

- Build your personal brand

The advent of social media makes it easy for anyone to become an industry expert. Start a blog, promote your work and engage with other influencers to develop your personal brand. You need to be careful here – there are a lot of people using Twitter to talk about how great they are, try and be different.

I hope these tips are helpful, if there are any other habits that you’ve used to achieve success I’d love to hear about them!

SELECT INTO vs INSERT INTO on Columnstore

This is one of the useful SQL tips from the article on SQLCentral.Com

http://www.sqlservercentral.com/articles/Performance+and+Tuning/126527/

SELECT INTO vs INSERT INTO on Columnstore