DATABASE FUNDAMENTALS
DATA WAREHOUSING AND DATA MINING
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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TRUE
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FALSE
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Either A or B
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None of the above
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Detailed explanation-1: -It is a variant of star schema. It uses highly structured dimensions. It follows parent-child relationship method while storing data in which child tables can have multiple parent table. Dimension tables in snowflake schema are in normalized form.
Detailed explanation-2: -The snowflake schema is a fully normalized data structure. Dimensional hierarchies (such as city > country > region) are stored in separate dimensional tables.
Detailed explanation-3: -A star schema has denormalized dimension tables, while a snowflake schema has normalized dimension tables. A star schema is easier to design and implement than a snowflake schema. A star schema can be more efficient to query than a snowflake schema, because there are fewer JOINs between tables.
Detailed explanation-4: -Star schemas denormalize the data, which means adding redundant columns to some dimension tables to make querying and working with the data faster and easier. The purpose is to trade some redundancy (duplication of data) in the data model for increased query speed, by avoiding computationally expensive join operations.
Detailed explanation-5: -Which of the following related to snowflake schema is true? Explanation: Snowflake schema is an arrangement of tables in a multidimensional database system. It contains Fact Tables connected to multi-dimension tables.