Friends,
I have never taken and also given an interview on SSAS(even on MSBI) with out the question “What is the difference between STAR and SNOWFLAKE Schema”. Before going to the differences lets have a look at what a schema is and the types.
Schema in relational database defines the tables, columns in each table, and the relationships between tables. It gives a clear picture about the tables present in the database how the tables are related to each other. There are mainly two types of schema(and ppl are adding one per day like STARFLAKE,GALAXY and so on .. but not to worry much about those) which are listed below.
1) Star
2) SnowFlake.
Lets discuss about each type in detail here.
Star –
This is the simplest Schema design available and in the star schema design, a single object (the fact table) sits in the middle and is radially connected to other surrounding objects (dimension lookup tables) like a star. Each dimension is represented as a single table. The primary key in each dimension table is related to a foreign key in the fact table. In simple when ALL the DIMENSION TABLES are DIRECTLY related to FACT TABLE then that Schema is called as Star Schema. PFB the Screenshot showing STAR Schema.
Snow Flake –
The snowflake schema is an extension of the star schema, where each point of the star explodes into more points. In a star schema, each dimension is represented by a single dimensional table, whereas in a snowflake schema, that dimensional table is normalized into multiple lookup tables, each representing a level in the dimensional hierarchy. When ALL the dimension tables are NOT directly related to FACT table then that type of schema is called as Snow Flake Schema. PFB Screenshot of Snow Flake Schema.
In snow flake schema fact table will be linked directly as well as there will be some intermediate dimension tables or Fact less Fact tables between fact and dimension tables.
That’s it .. Happy Coding !!
Regards,
Roopesh Babu V
росгвардия дачи росгвардия дачи .
farmacie online affidabili: Cialis generico recensioni – acquistare farmaci senza ricetta
buy lasix online: buy furosemide – furosemida 40 mg
neurontin price south africa: neurontin 100mg tab – neurontin 300mg caps
accutane 40mg for sale – buy avlosulfon 100mg pill buy deltasone 10mg pill
https://ventolininhaler.pro/# where to buy ventolin generic
prednisone coupon: prednisone medicine – buying prednisone on line
pharmacy website india: Online medication home delivery – cheapest online pharmacy india
Профессиональный сервисный центр по ремонту планшетов в том числе Apple iPad.
Мы предлагаем: сервисы айпад в москве
Наши мастера оперативно устранят неисправности вашего устройства в сервисе или с выездом на дом!
http://indiadrugs.pro/# online pharmacy india
http://mexicanpharma.icu/# pharmacies in mexico that ship to usa
Купить диплом магистра оказалось возможно, быстрое обучение и диплом на руки
modafinil usa – buy generic meloset for sale cost meloset 3mg
купить 1С купить 1С .
Рекомендации по безопасной покупке диплома о высшем образовании
выведение из запоя на дому круглосуточно выведение из запоя на дому круглосуточно .
Рекомендации по безопасной покупке диплома о высшем образовании
сервисный центр по ремонту телефонов