Discuss the advantages & Disadvantages of star & snowflake
schema?
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Answer / alhad kulkarni
The question is Advantages and Disadvantages, not What is
Star or Snowflake.
Star Adv: Reduced Joins, Faster Query Operation.
Snow Adv: Distributed data, Easier to obtain fact-less data
e.g. Orders Shipped across one Quarter.
Star DisAdv: Bigger table sizes, Too many rows in Fact Table
Snow DisAdv: More number of joins, Slower Query operation,
| Is This Answer Correct ? | 78 Yes | 1 No |
Answer / ravi sadanand
Star Schema: It is fully denormalized schema.the diagram of
fact table with dimension tables resembles a star that's
why it is called star schema.All the dimensions will be in
2nd normal form.
Snow flow schema:In this all dimensions will be in
normalized form.that's why it is called normalized star
schema.For each attribut a seperate table will be
created.As there is a possibility for more number of
joins,obviously the performance will be degraded.
| Is This Answer Correct ? | 34 Yes | 11 No |
Answer / susanta karmakar
Star Schema: A star schema is a specialized design that
consists of multiple dimension tables, which describe
aspects of a business, and one fact table, which contains
the facts about the business.For example, if you have a
mail-order business selling books, some dimension tables are
customers, books, catalogs, and fiscal years. The fact table
contains information about the books that are ordered from
each catalog by each customer during the fiscal year.
| Is This Answer Correct ? | 8 Yes | 7 No |
Answer / hania
Star Schama : easy for users to understand, optimize navigation and more suitable for query processing, and works faster.
Disadvantages: Dimension table have greater rows, large fact table
| Is This Answer Correct ? | 2 Yes | 2 No |
Answer / krishna
in starschema the fact is denormalised ...all dimension
tables are normalise..there will be primary foreignkey
relation ship between fact and dimension tables.
for better perfomance we use starschema when compare to
snow flake schema ..where fact table and dimension tables
are normalised...for every dimension table tthere will be a
look table ..we have to dig from top to bottom in the
snowflake schema.
| Is This Answer Correct ? | 18 Yes | 28 No |
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