4.Explain Snowflkeschema ?
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Answer / prodyot sarkar
A snowflake schema is a variation on the star schema, in which very large dimension tables are normalized into multiple tables. Dimensions with hierarchies can be decomposed into a snowflake structure when you want to avoid joins to big dimension tables when you are using an aggregate of the fact table. For example, if you have brand information that you want to separate out from a product dimension table, you can create a brand snowflake that consists of a single row for each brand and that contains significantly fewer rows than the product dimension table.
Advantages of Using the Snowflake Schema
i)in some cases may improve performance because smaller tables are joined,
ii)is easier to maintain
iii)increases flexibility.
Disadvantages of Using the Snowflake Schema
i)increases the number of tables an end-user must work with
ii)makes the queries much more difficult to create because more tables need to be joined.
| Is This Answer Correct ? | 4 Yes | 0 No |
Answer / nrkreddy
snow flake shema is nothing but fact table is sourrended by
dimension table getting the lowest level of the
information
snow flake sehema is used for getting the details From
lowest level of Grunularity
in the sense we will get the data from the detailed level
For example : TIME
a Fact table is associated with TIME Dimension up to month
granulary in the sence this DIM table having
year-->Quater-->month
beut we need the information Up to a day in this senario we
will go Snowflake shema is sliced deeply up to the Day
year-->Quater-->month-->week-->Day
here the dimension table
| Is This Answer Correct ? | 2 Yes | 0 No |
Answer / sanjeev_mis
One dimension is not connected directly to the fact table, instead, it is connected through another dimension table.
... SANJEEV SHARMA
| Is This Answer Correct ? | 2 Yes | 1 No |
In snowflake schema the dimension table(denormalized table)
will be further divided into one or more dimentions
(normalized tables) to organize the infomation in a better
structural format.To design snowflake we should first
design star schema design.
| Is This Answer Correct ? | 1 Yes | 0 No |
Answer / sudheer.r
snowflake schema is centrally located fact table .and
surrounded by normalized dimension tables..
in snowflake compare to dimensions and ffact table
dimensions are small.dimensions are more compare to ster
chema .. snow flake shema very dificult to understand ...
| Is This Answer Correct ? | 3 Yes | 3 No |
Each Dimension table has been split into more than one
dimension and connected with centralized fact table. It has
bigger size than star schema. Dimensions are sliced
deeply with the business requirements.
But it is tough to understandable since it has more tables
| Is This Answer Correct ? | 0 Yes | 0 No |
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