问题
问答题 简答题
数据库应用环境下，如何用实体联系方法和基于3NF的方法进行概念模型的设计？
答案
参考答案：
进行概念模型设计时，要自底向上，逐层归并，构造各子实体联系图，到顶层得到系统的实体联系草图，再进行化简与优化，最后得到实体联系图。具体可以分为：识别实体；识别联系；完成实体联系草图；将属性归到实体；进行数据分析；完成修正的实体联系图。
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数据库应用环境下，如何用实体联系方法和基于3NF的方法进行概念模型的设计？
参考答案：
进行概念模型设计时，要自底向上，逐层归并，构造各子实体联系图，到顶层得到系统的实体联系草图，再进行化简与优化，最后得到实体联系图。具体可以分为：识别实体；识别联系；完成实体联系草图；将属性归到实体；进行数据分析；完成修正的实体联系图。
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| ( ) 1. A. Breakfast ( ) 2. A. evening ( ) 3. A. morning ( ) 4. A. with ( ) 5. A. angrier ( ) 6. A. carefully ( ) 7. A. also ( ) 8. A. Though ( ) 9. A. having ( ) 10. A. sad | B. Lunch B. night B. noon B. to B. hungrier B. happily B. too B. So B. choosing B. sick | C. Dinner C. noon C. evening C. of C. sad C. wrongly C. yet C. Since C. taking C. angry | D. Supper D. morning D. night D. for D. boring D. correctly D. as well D. If D. eating D. sorry |