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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Many-to-many
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One-to-one
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One-to-many
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All of the above.
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Detailed explanation-1: -A star schema can have any number of dimension table s. The branches at the end of the links connecting the tables indicate a many-to-one relationship between the fact table and each dimension table.
Detailed explanation-2: -As a rule, each foreign key of the fact table must have its counterpart in a dimension table. Additionally, any table in a dimensional database that has a composite key must be a fact table. This means that every table in a dimensional database that expresses a many-to-many relationship is a fact table.
Detailed explanation-3: -The star schema separates business process data into facts, which hold the measurable, quantitative data about a business, and dimensions which are descriptive attributes related to fact data. Examples of fact data include sales price, sale quantity, and time, distance, speed and weight measurements.
Detailed explanation-4: -The Star Schema Design Pattern. A star schema consists of one fact table, and one or more dimension tables. The fact table contains information about changes. In the most basic kind of fact table, each row represents a transaction.