Titlebook: Beginning Database Design; From Novice to Profe Clare Churcher Book 2007 Clare Churcher 2007 Access.SQL.database.database design.databases.

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Normalization,We are doing pretty well at designing a database. So far, you have learned how use cases and a data model can help you understand many of the complexities of the actual problem you are trying to represent. In the previous chapter, you saw how to represent the main parts of the data model in a relational database. To recap:

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Yi Ding,Yonghua Song,Changzheng Shaosarily the correct one. Often a table or spreadsheet is designed to mimic a possible data entry screen or a hoped-for report. This practice may be adequate for solving the immediate problem (e.g., storing the data somewhere); however, mimicking a data entry screen or report in your database design o

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Fatih Yilmaz,Yunus Emre Yuksel,Murat Ozturko make sure we really understand the problem. This may sound obvious, but it is surprising how often people set about implementing a database before they understand the problem completely. There are two things we need to do: understand what tasks all the people who will use the system need to carry

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https://doi.org/10.1007/978-3-8349-3958-6ry out. Tasks were represented with use cases, and a simple data model was developed to represent the required data. In Chapter 4, you saw that a great deal can be learned about a problem by questioning some of the details of simple relationships, particularly the number of objects involved at each

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Waldemar Cruz,Fanghui Liu,Laurent Michelmight like. We might find that we have some objects for which some of the attributes do not really apply. For example, if we have a class to record information about all the people associated with a company, we might find that some have hourly pay rates while others have annual salaries. In many res

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Eldan Cohen,J. Christopher Beckloped an initial data model. By looking carefully at the details of the model, we were able to develop questions to help understand further subtleties and complexities about the real-world problem. We then looked at a number of situations that occur in many models in the hope that these would be use