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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Address
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Body Mass Index
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Last Name
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Date of Birth
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Detailed explanation-1: -What is a Slowly Changing Dimension? A Slowly Changing Dimension (SCD) is a dimension that stores and manages both current and historical data over time in a data warehouse. It is considered and implemented as one of the most critical ETL tasks in tracking the history of dimension records.
Detailed explanation-2: -Some examples of typical slowly changing dimensions are entities as names of geographical locations, customers, or products. Some scenarios can cause referential integrity problems. For example, a database may contain a fact table that stores sales records.
Detailed explanation-3: -Type 3 Slowly Changing Dimensions This type of slowly changing dimension is used when a change in a dimension value must be tracked but the old value must be retained as part of the record, usually for reporting. For example, a type 3 slowly changing dimension might be useful in a sales force realignment.