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按规范设计的方法将数据库设计分为六个阶段：1．需求分析。2．概念结构设计。3．逻辑结构设计。4．数据库物理设计。5．数据库实施。6．数据库运行和维护。针对关系数据库设计的逻辑结构设计，回答下述问题： ①逻辑设计的基本任务 ②逻辑设计过程中，如何将E-R模型向关系数据模型转换 ③关系数据库逻辑设计的步骤和内容

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Design Competition Professional College is 5 years old ! Let’s begin the celebration by a design competition. All students are invited to submit designs for the following: 1. The fifth year anniversary souvenir (e. g. Mugs, Windbreaker, raincoat, coaster, notebook, etc., limited only by you imagination. ) 2. Professional College T-shirt. 3. Professional College Logo. 4. Professional College Song. 5. Professional College Cheer. Deadline: May 15, midnight Submission: College Office or 108 pigeon hole Winner will be selected by the management team and student representatives. For each catalogue, there will be a prize of 200 yuan. Hurry up! I have already received one design! "Share the joy with your friends ! Share the pride of our Professional College!\ Where can the students submit their own designs ______ or 108 pigeon hole.

“无定式”的造园基本法则是选址因地制宜、从环境出发，风格设计因人而异，突出个性。（）

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