star and snowflake schema?
Answers were Sorted based on User's Feedback
Answer / rr
Star schema has denormalised dimension tables connected to
a single fact table.
Snow flake schema has normalised dimension tables.
Is This Answer Correct ? | 8 Yes | 2 No |
Answer / sathish
Star Schema
Star Schema is the type of modeling where we follow the
complete de-normalization process.A star schema contains
multiple dimensions which share the same fact table.
Say per example in the sales analysis star schema, the
actual sales goes into fact and the customer, product, date,
sales force information goes as dimensions.
Snowflake Schema
In order to strike a balance between 3rd normal form data
model and star schema, we have snow flake schema which is
more of normalized star schema. Even in snow flake we will
have the fact and dimension only big difference is the
dimension tables are normalized.
Is This Answer Correct ? | 2 Yes | 0 No |
Answer / deepa
star schema has fact table in the middle and dimensions
around it which are denormalized.
normalized form of star schema is called snow flake star
schema.
Is This Answer Correct ? | 1 Yes | 0 No |
Answer / srikanth nallapati
star schema is a centrelized fact table surrounded by
dimention tables.where dimention tables are denormalized .
here the number of joins are less then the query
performence good.
but in snow flake schema dimention tables are normalized
here we can view lowest level granularity .here the number
of joins are high comparing to snowelake schema then
automatically performence is degread.
Note:performence is depending upon the requirement
Is This Answer Correct ? | 1 Yes | 0 No |
Answer / tamilarasan m
Star fact table join with all the dimension tables.All the
dimension tables are denormalized.ain Snowflake dim table
join with another dimension.All the dimension r normalized
Is This Answer Correct ? | 0 Yes | 0 No |
Answer / mohammed
Snowflake is an extension of star schema, where star schema
with each dimension is typically stored in one table.
Is This Answer Correct ? | 0 Yes | 1 No |
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