Snowflake Schema — Learn free

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Questions 1–10 of 10

1. What does a snowflake schema have in common with a star schema?
Question 1A. Both store facts inside the dimension tablesB. Both have a fact table in the middle with dimensions around itC. Both avoid any joins in queriesD. Both belong to Bill Inmon's approachE. Both are used only in OLTP systems
2. What distinguishes a snowflake schema from a star schema?
Question 2A. The fact table is normalised into several fact tablesB. Dimensions can be normalised further into multiple sub-dimensionsC. There are no dimensions at allD. The fact table is replaced by a cubeE. Dimensions are denormalised into a single wide table
3. How does normalising dimensions into sub-dimensions affect a report query in a snowflake schema?
Question 3A. It removes the need for joinsB. It requires multiple joins to reach a conclusive resultC. It makes the query identical to a star schema queryD. It restricts the query to one dimensionE. It requires the query to be written in NoSQL
4. In the snowflake schema example, into which sub-dimensions is the Location dimension normalised?
Question 4A. Year, Quarter and MonthB. Category, Brand and ModelC. State, City and Postal CodeD. Region, Country and ContinentE. Store, Aisle and Shelf
5. Whose data warehousing approach does the snowflake schema belong to?
Question 5A. Ralph KimballB. Bill InmonC. Dan LinstedtD. Edgar CoddE. Lars Rönnbäck
6. In the snowflake schema example, what is the name of the fact table?
Question 6A. LocationB. StateC. SalesD. CityE. Postal Code
7. According to Ralph Kimball, what modelling must be used for data warehouses and data marts?
Question 7A. Third Normal Form throughoutB. Dimensional modelling with star and snowflake schemasC. Hub, link and satellite modellingD. Document modellingE. Graph modelling
8. Which statement about joins in a snowflake schema versus a star schema is correct?
Question 8A. A star schema needs multiple joins per dimension; a snowflake needs oneB. A star schema has one direct join per dimension; a snowflake may need multiple joins through sub-dimensionsC. Neither schema requires joinsD. Both always require exactly two joinsE. Joins are only needed in OLTP systems
9. What is a sub-dimension in a snowflake schema?
Question 9A. A smaller fact tableB. A table produced by normalising a dimension further, such as City within LocationC. A pre-aggregated cubeD. A copy of the fact table for one departmentE. A dimension with no primary key
10. In which kinds of data store is the snowflake schema applied?
Question 10A. Data warehouses and data martsB. OLTP order-entry systemsC. Raw data lakesD. Message queuesE. Web servers