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Strategy

Star schema is a denormalized model with one or more fact table is surrounded by number of fact table. The whole diagram itself it depicts a star called star schema.Advantage is star schema:
1.Contains lesser no of joins
2.Contains lesser no of queries, so queries result fastly.

Disadvantage of star schema:
If the dimension table is very huge in that case data redundancy will be there.Snowflake schema is based on normalization like normalize the dimension table to remove redundancy and dependancy. If star schema consists of a huge dimension table then we will broken that table into a no of dimension table.

Advantage of snow flake schema:

1.Non redundant data
2.Flexible
3.Easy to maintain

Disadvantage of snowflake schema:
1.Query performance go down as it needs more join to retrieve data.

Basically based on business needs and if the dimensional table is huge,  go for snow flake schema and if there is one denormalized dimensional table go for star schema

OLTP(Online Transactional Processing)  is a transactional system, data oriented model. It always contain data for few weeks or month. It is always up to date and shows current status of each business transaction .It is used to store few transactional data without any processing done on it. This system often use normalized schema.

Where Data Warehouse is a subject oriented,integrated,non volatile, time variant model. It is designed to contain historical data derived from transaction data(operational system),used for multi dimensional analysis, facilitate adhoc queries, deals with denormalized data. This system always contain years of data.

Both the systems follow a different operational logic, typical operation, it is better to maintain/access separately.

This morning I started for my class at 7:15 AM driving my GETZ Prime. It was a usual cold winter morning in Bangalore in early hour of Saturday. Road was supposed to be empty. I overtook few autos, then a Ford IKON, which was irritatingly driving slowly. I suddenly accelerated my car to avoid entering late in the class. As soon as I entered Indiranagar 100ft road, I found a small crowd gathered in the middle of the road. That instantly reminds me the danger of driving and crossing Bangalore road. I saw a Honda city crashed, and 3 human bodies lying in front of that.

After that scene, I could not  be able to gather enough courage to drive above 30KMPH. Bangalore road is full of  death trap. You never know when a divine call will come for you in the name of a hit and run case!

Indians are finally in Oscar once again after legendary Satyajit Roy. Slumdog Millionaire bagged 10 Oscar nominations and musician AR Rahman alone bagged 3 nominations for himself. Though I have not seen the movie yet, I am quite excited and happy about Mumbai, the place primarily portrait in the movie. This City never stops to surprise us. Mumbai has one of the largest slums of the world. It also houses world’s top billionaires, famous BollyWood stars. Mumbai carries millions of hopes for young and educated Indians, budding artists, businessmen, and entrepreneurs. Mumbai probably is not as planned as NY, London and Paris, but Mumbai has a soul which is very difficult to find anywhere else in the world. Where on earth you will find billionaires and beggars sharing the same local train?  After brutal terror attack on 26/11, Mumbai is in headline again. This time is for all good reasons!