Bottom up design first defines the required

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Bottom-updesign:first defines the required attributes and thengroups the attributes to form entities.Although the two methodologies tend to be complementary, database designers who deal with smalldatabases with relatively few entities, attributes, and transactions tend to emphasize the bottom-upapproach. Database designers who deal with large, complex databases usually find that a primarilytop-down design approach is more appropriate.In spite of the frequent arguments concerning the best design approach, perhaps the top-down vs.bottom-up distinction is quite artificial. The text's note is worth repeating:NOTEEven if a generallytop-down approach is selected, the normalization process that revisesexisting table structures is (inevitably) a bottom-up technique. E-R models constitute a top-down process even if the selection of attributes and entities may be described as bottom-up.Since both the E-R model and normalization techniques form the basis for most designs, thetop-down vs. bottom-up debate may be based on a distinction without a difference.Problem Solutions1.The ABC Car Service & Repair Centers are owned by the SILENT car dealer; ABC servicesand repairs only SILENT cars. Three ABC Car Service & Repair Centers provide service andrepair for the entire state.Each of the three centers is independently managed and operated by a shop manager, areceptionist, and at least eight mechanics. Each center maintains a fully stocked partsinventory.Each center also maintains a manual file system in which each car’s maintenance history iskept: repairs made, parts used, costs, service dates, owner, and so on. Files are also kept totrack inventory, purchasing, billing, employees’ hours, and payroll.You have been contacted by the manager of one of the centers to design and implement acomputerized system. Given the preceding information, do the following:107
Chapter 9 Database Designa.Indicate the most appropriate sequence of activities by labeling each of the following stepsin the correct order. (For example, if you think that “Load the database.” is theappropriate first step, label it “1.”)__7__Normalize the conceptual model._3___Obtain a general description of company operations.__9__Load the database.__4__Create a description of each system process.__1_Test the system._6___Draw a data flow diagram and system flowcharts. _5___Create a conceptual model, using ER diagrams. _10__Create the application programs. _2___Interview the mechanics. __8__Create the file (table) structures. __1__Interview the shop manager.ANALYSIS 1. Interview the shop manager2. Interview the mechanics 3. Obtain a general description of company operations 4. Create a description of each system processDESIGN 5. Create a conceptual model, using E-R diagrams 6. Draw a data flow diagram and system flow charts 7. Normalize the conceptual modelIMPLEMENTATION 8. Create the table structures 9. Load the database 10. Create the application programs 11. Test the system.

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