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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It is designed to support query
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It is designed to support storage
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It is entity-relationship modeling
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It does not need normalization
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Detailed explanation-1: -Data Dimensional Modelling (DDM) is a technique that uses Dimensions and Facts to store the data in a Data Warehouse efficiently. It optimises the database for faster retrieval of the data. Dimensional Models have a specific structure and organise the data to generate reports that improve performance.
Detailed explanation-2: -The purpose of dimensional modeling is to enable business intelligence (BI) reporting, query, and analysis. The key concepts in dimensional modeling are facts, dimensions, and attributes. There are different types of facts (additive, semiadditive, and nonadditive), depending on whether they can be added together.
Detailed explanation-3: -Benefits of the dimensional model are the following: Understandability. Compared to the normalized model, the dimensional model is easier to understand and more intuitive. In dimensional models, information is grouped into coherent business categories or dimensions, making it easier to read and interpret.
Detailed explanation-4: -It is a numeric attribute of a fact, representing the performance or behavior of the business relative to the dimensions. Considering the relational context, there are two basic models which are used in dimensional modeling: Star Model. Snowflake Model.