Why Star Schema is de-normalized? Please explain in detail
probably with some examples.
Answers were Sorted based on User's Feedback
Answer / kumar
Star Schema is centally Located by Fact Table surrounded by
Dimension Tables, hence it resembles Star so we call it
as "Star Schema"
Here We use the De-Normalized tables, If we use Normalizewd
tables that prefer the Snow-Flake Schema.
In Star Schema we have the less no. of tables, so we have
the duplicate records with non key attributes.
For further Reference, Please go through the below URL.
http://datawarehouse4u.info/Data-warehouse-schema-
architecture-star-schema.html
| Is This Answer Correct ? | 9 Yes | 1 No |
Answer / aq
Because, we use Star schema to analyse the data and for that we need fast access of that data.
if the schema is normalized then it will have more joins and will take more time retrieve the data from source, which will cause the reporting / analysis slow.
Hence to faster access of the data Star Schema is de-normalized
| Is This Answer Correct ? | 2 Yes | 0 No |
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