Why are data in a data warehouse stored in unnormalized tables?
What will be an ideal response?
Normalizing data in an operational database is necessary to reflect accurately the dynamic interactions among entities. While a fully normalized database provides the flexible model needed for supporting multiple users in operations environment, it also adds to complexity that translate into performance inefficiency. Because of the vast size of a data warehouse, such inefficiency can be devastating. A three-way join between tables in a large data warehouse may take an unacceptably long time to complete and may be unnecessary. In the data warehouse model, the relationship among attributes does not change. Because historical data are static in nature, nothing is gained by constructing normalized tables with dynamic links.
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Which of the following statements is false?
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If a cell in a table is too narrow for text that you type, what happens?
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When two paths of execution run simultaneously but in separate memory spaces, they are know as ________. When they share memory, they are known as .
Fill in the blank(s) with the appropriate word(s).
Case-Based Critical Thinking QuestionsCase 4-1Rita would like to create an animation for a Web site that she is developing for a client. She has come to you for help in using special layers to create the animation. You begin by reviewing the types of layers that can be used. During a demonstration, Rita explains that the object moving across the screen moved too quickly, so that she could barely see it. You explain that you can change the object's speed by modifying the motion tween's properties using the ____.
A. Motion Path B. Motion Editor C. Movie Path D. Movie Editor