BLOGS

ByHariharan Rajendran

Vertipaq

Vertipaq is an engine which was found in Power Pivot for Analysis server in SQL Server 2008 R2. Basically, it is used for data compression. Data retrieval and calculations are happening at much faster rate as it holds the compressed data in memory.  It is also called xVelocity and it has been added to SQL Server 2012. As a result, it is delivering very huge performance improvements for data warehouse and business intelligence solutions.

Columnstore index using this compression algorithm technology.

This algorithm using following compression techniques.

  1. Value Encoding
  2. Dictionary Encoding
  3. Run Length Encoding (RLE)

Check this link, for detailed information about VertiPaq Compression techniques.

ByHariharan Rajendran

Data Storage Format in Columnstore Index

Go through my previous article purpose of columnstore index.

Normally SQL Server stores the data in pages in a row based manner for tables (heaps) and B-tree indexes. This is the traditional approach and technically this is called “Row store”.

Column store is something like turning traditional storage model into 90 degrees. In this approach, all the values in single column will be in compressed form. Column store index stores each column in a separate set of disk pages which is different from the traditional storage format.

Let’s see an example,

ID Name Department
1 xyz Production
2 Robert Information Technology
3 Mary Sales
4 John Account

 

Row store
1 xyz Production
2 Robert Information Technology
3 Mary Sales
4 John Account

 

Column Store
1 2 3 4
Xyz Robert Mary John
Production Information Technology Sales Account

Column store index is more compressed than the row store. This can understand by seeing above examples. In row store format we have different data types involved in a single row (ID is Integer, Name is string, Department is string). Row store method trying to compress the different data type fields, but in column store, all the values in a same data type so it is easy to compress the data.

Data Compression percentage of column store is greater than the row store.

 

ByHariharan Rajendran

Basic Concepts of Power BI

Check my previous post about introduction to Power BI before going through this article.

Creating a report and dashboards are very easy in Power BI by simply pointing to the correct data source.

Levels in Power BI,

1. Create a dataset
2. Create a report on top of above dataset
3. Create a dashboard – Just pin a charts to display in dashboard from report.

Power BI is an application which we can use in online as well as in desktop. The steps provided in my previous article (Link) is for online version of Power BI.

To download the desktop version, click here. It has more options compare than online version.

Power BI has gateways which helps to keep the data fresh by connecting the on-premises data sources. It provides the flexibility to individuals as well as organization.

ByDr. SubraMANI Paramasivam

7 key habits, practice & experience, which made Bill Gates succeed

I just flipped through my phone and found this amazing article which might be a great energy re-charge for many youngsters today. This clearly talked about the key habits, practise and experience from Bill Gates that helped him succeed. This is just a simple formulae for all of us to do, what we do should have hard core dedication & hard work to succeed. The main 7 key points highlighted are

  1. Get in early – and learn
  2. Seek forgiveness, not permission
  3. Value your work
  4. Learning matters more than school
  5. When you’re in charge, take charge
  6. Be the guy who predicts the future
  7. Take on a big enough mission.

What a great re-invention that we should really apply in our day to day life. I sincerely advise and suggest to all of you who don’t do this or have done this in the past but don’t do it anymore, to restart in doing the same.

All the very best.

 

ByHariharan Rajendran

Introduction to Power BI

Power BI is one of the best visualization tool and it can be used by anyone. Initially this tool was available for office 365 SharePoint site. It was something like an add-on but now they have upgraded and it is available externally.

Power BI team from Microsoft has put their ideas and innovations to make this tool available to everyone and it is not  required much technical knowledge to use.

There are lots of improvement has been taking place from day one of power BI by Microsoft power BI team.

Steps to Use Power BI

  1. Visit https://powerbi.microsoft.com/
  2. Scroll down and look for option “Use it free”
  3. Enter work email (xxxxx@xxxx.com), it won’t support personal email
  4. Click “Use it free” and email will be received from power BI and follow the instructions.