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<div id="pf1" class="pf w0 h0" data-page-no="1"><div class="pc pc1 w0 h0"><img class="bi x0 y0 w1 h1" alt="" src="https://static.pudn.com/prod/directory_preview_static/6275e22f602a7856fe2a86a9/bg1.jpg"><div class="c x0 y1 w2 h2"><div class="t m0 x1 h3 y2 ff1 fs0 fc0 sc0 ls0 ws0">数据库系统概论复习资料：</div><div class="t m0 x2 h3 y3 ff1 fs0 fc0 sc0 ls0 ws0">第一章<span class="sc1">：</span></div><div class="t m0 x3 h3 y4 ff1 fs0 fc0 sc1 ls0 ws0">一选择题：</div><div class="t m0 x3 h3 y5 ff2 fs0 fc0 sc1 ls0 ws0">1<span class="ff1">．在数据管理<span class="_ _0"></span>技术的发展过<span class="_ _0"></span>程中，经历了人工<span class="_ _0"></span>管理阶段、文件系<span class="_ _0"></span>统阶段和数据库系<span class="_ _0"></span>统阶段。在这几个</span></div><div class="t m0 x3 h3 y6 ff1 fs0 fc0 sc1 ls0 ws0">阶段中，<span class="fc1">数据独立性最高的是 阶段。</span></div><div class="t m0 x3 h3 y7 ff2 fs0 fc0 sc1 ls0 ws0"> <span class="fc1"> A<span class="ff1">．数据库系统<span class="fc0"> </span></span></span>B<span class="ff1">．文件系统 </span>C<span class="ff1">．人工管理 </span>D<span class="_ _0"></span><span class="ff1">．数据项管理 答案：</span>A</div><div class="t m0 x3 h3 y8 ff2 fs0 fc0 sc1 ls0 ws0">2<span class="ff1">．数据库的概念模型独立于 <span class="_ _0"></span> 。</span></div><div class="t m0 x3 h3 y9 ff2 fs0 fc0 sc1 ls0 ws0"> <span class="fc1">A<span class="ff1">．具体的机器和<span class="_ _1"> </span></span>DBMS </span> B<span class="ff1">．</span>E-R<span class="_ _1"> </span><span class="ff1">图 </span>C<span class="ff1">．信息世界 <span class="_ _0"></span></span>D<span class="ff1">．现实世界 答案：</span>A</div><div class="t m0 x3 h3 ya ff2 fs0 fc0 sc1 ls0 ws0">3<span class="ff1">．数据库的基本特点是 。</span></div><div class="t m0 x3 h3 yb ff2 fs0 fc0 sc1 ls0 ws0"> <span class="_ _0"></span> A<span class="_ _0"></span><span class="ff1">．</span>(1)<span class="_ _0"></span><span class="ff1">数据可<span class="_ _0"></span>以共享<span class="_ _0"></span></span>(<span class="_ _0"></span><span class="ff1">或数据结<span class="_ _0"></span>构化<span class="_ _0"></span></span>)<span class="_ _0"></span> <span class="_ _0"></span> (2)<span class="_ _0"></span><span class="ff1">数据独立<span class="_ _0"></span>性 <span class="_ _0"></span> <span class="_ _2"></span></span>(3)<span class="ff1">数据<span class="_ _0"></span>冗余大，<span class="_ _0"></span>易移植 <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _3"></span></span>(4)<span class="ff1">统一<span class="_ _0"></span>管</span></div><div class="t m0 x3 h3 yc ff1 fs0 fc0 sc1 ls0 ws0">理和控制</div><div class="t m0 x3 h3 yd ff2 fs0 fc0 sc1 ls0 ws0"> <span class="_ _0"></span> B<span class="_ _0"></span><span class="ff1">．</span><span class="fc1">(1)<span class="_ _0"></span><span class="ff1">数据可<span class="_ _0"></span>以共享<span class="_ _0"></span></span>(<span class="_ _0"></span><span class="ff1">或数据结<span class="_ _0"></span>构化<span class="_ _0"></span></span>) <span class="_ _0"></span> <span class="_ _0"></span> (2)<span class="_ _0"></span><span class="ff1">数据独立<span class="_ _0"></span>性 <span class="_ _0"></span> <span class="_ _0"></span></span>(<span class="_ _0"></span>3)<span class="ff1">数据冗<span class="_ _0"></span>余小，易<span class="_ _0"></span>扩充 <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _3"> </span></span>(<span class="_ _0"></span>4)<span class="ff1">统一管</span></span></div><div class="t m0 x3 h3 ye ff1 fs0 fc1 sc1 ls0 ws0">理和控制</div><div class="t m0 x3 h3 yf ff2 fs0 fc0 sc1 ls0 ws0"> <span class="_ _0"></span> C<span class="_ _0"></span><span class="ff1">．</span>(1)<span class="_ _0"></span><span class="ff1">数据可以<span class="_ _0"></span>共享<span class="_ _0"></span></span>(<span class="_ _0"></span><span class="ff1">或数据<span class="_ _0"></span>结构化<span class="_ _0"></span></span>)<span class="_ _0"></span> <span class="_ _0"></span>(2)<span class="_ _0"></span><span class="ff1">数据互<span class="_ _0"></span>换性 <span class="_ _0"></span> <span class="_ _0"></span></span>(3)<span class="_ _0"></span><span class="ff1">数据冗余<span class="_ _0"></span>小，易<span class="_ _0"></span>扩充 <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _3"></span></span>(4)<span class="_ _0"></span><span class="ff1">统一管</span></div><div class="t m0 x3 h3 y10 ff1 fs0 fc0 sc1 ls0 ws0">理和控制</div><div class="t m0 x3 h3 y11 ff2 fs0 fc0 sc1 ls0 ws0"> D<span class="ff1">．</span>(<span class="_ _0"></span>1)<span class="ff1">数据非结构化 <span class="_ _3"></span></span>(2)<span class="ff1">数据独立性 <span class="_ _0"></span></span>(3)<span class="ff1">数据冗余小，易扩充 <span class="_ _3"></span></span>(4)<span class="ff1">统一管理和控</span></div><div class="t m0 x3 h3 y12 ff1 fs0 fc0 sc1 ls0 ws0">制 答案：<span class="ff2">B</span></div><div class="t m0 x3 h3 y13 ff2 fs0 fc0 sc1 ls0 ws0">4. <span class="ff1">是存储在计算机内有结构的数据的集合。</span></div><div class="t m0 x3 h3 y14 ff2 fs0 fc0 sc1 ls0 ws0"> A<span class="ff1">．数据库系统 </span><span class="fc1">B<span class="ff1">．数据库<span class="fc0"> </span></span></span>C<span class="_ _0"></span><span class="ff1">．数据库管理系统 </span>D<span class="ff1">．数据结构 答案：</span>B</div><div class="t m0 x3 h3 y15 ff2 fs0 fc0 sc1 ls0 ws0">5<span class="ff1">．数据库中存储的是 。</span></div><div class="t m0 x3 h3 y16 ff2 fs0 fc0 sc1 ls0 ws0"> A<span class="ff1">．数据 <span class="_ _0"></span></span>B<span class="ff1">．数据模型 </span><span class="fc1">C<span class="ff1">．数据以及数据之间的联系<span class="fc0"> </span></span></span>D<span class="ff1">．信息 答案：</span>C</div><div class="t m0 x3 h3 y17 ff2 fs0 fc0 sc1 ls0 ws0">6. <span class="ff1">数据库中，数据的物理独立性是指 。</span></div><div class="t m0 x3 h3 y18 ff2 fs0 fc0 sc1 ls0 ws0"> A<span class="ff1">．数据库与数据库管理系统的相互独立 </span>B<span class="ff1">．用户程序与<span class="_ _1"> </span></span>DBMS<span class="_ _1"> </span><span class="ff1">的相互独立</span></div><div class="t m0 x3 h3 y19 ff2 fs0 fc0 sc1 ls0 ws0"> <span class="_ _0"></span> C<span class="_ _0"></span><span class="ff1">．<span class="fc1">用<span class="_ _0"></span>户的应用<span class="_ _0"></span>程序与存<span class="_ _0"></span>储在磁盘<span class="_ _0"></span>上数据库<span class="_ _0"></span>中的数据<span class="_ _0"></span>是相互<span class="_ _0"></span>独立的<span class="_ _3"></span></span> <span class="_ _0"></span> </span>D<span class="_ _0"></span><span class="ff1">．应用程<span class="_ _0"></span>序与数据<span class="_ _0"></span>库中数据<span class="_ _0"></span>的</span></div><div class="t m0 x3 h3 y1a ff1 fs0 fc0 sc1 ls0 ws0">逻辑结构相互独立 答案：<span class="ff2">C</span></div><div class="t m0 x3 h3 y1b ff2 fs0 fc0 sc1 ls0 ws0">7. <span class="ff1">．数据库的特点之一是数据的共享，严格地讲，这里的数据共享是指 。</span></div><div class="t m0 x3 h3 y1c ff2 fs0 fc0 sc1 ls0 ws0"> A<span class="ff1">．同一个应用中的多个程序共享一个数据集合 </span>B<span class="ff1">．多个用户、同一种语言共享数据</span></div><div class="t m0 x3 h3 y1d ff2 fs0 fc0 sc1 ls0 ws0"> <span class="_ _4"></span> <span class="_ _2"></span> <span class="_ _2"></span> <span class="_ _0"></span>C<span class="_ _4"></span><span class="ff1">．<span class="_ _2"></span>多<span class="_ _2"></span>个<span class="_ _2"></span>用<span class="_ _2"></span>户<span class="_ _4"></span>共<span class="_ _2"></span>享<span class="_ _2"></span>一<span class="_ _2"></span>个<span class="_ _2"></span>数<span class="_ _2"></span>据<span class="_ _4"></span>文<span class="_ _0"></span>件<span class="_ _4"></span> <span class="_ _2"></span> <span class="_ _3"></span></span>D<span class="_ _0"></span><span class="ff1">．<span class="_ _2"></span><span class="fc1">多<span class="_ _4"></span>种<span class="_ _0"></span>应<span class="_ _4"></span>用<span class="_ _2"></span>、<span class="_ _2"></span>多<span class="_ _2"></span>种<span class="_ _2"></span>语<span class="_ _2"></span>言<span class="_ _4"></span>、<span class="_ _2"></span>多<span class="_ _2"></span>个<span class="_ _2"></span>用<span class="_ _2"></span>户<span class="_ _2"></span>相<span class="_ _4"></span>互<span class="_ _0"></span>覆<span class="_ _4"></span>盖<span class="_ _2"></span>地<span class="_ _2"></span>使<span class="_ _2"></span>用<span class="_ _2"></span>数<span class="_ _2"></span>据<span class="_ _4"></span>集<span class="_ _2"></span>合</span></span></div><div class="t m0 x3 h3 y1e ff1 fs0 fc0 sc1 ls0 ws0">答案：<span class="ff2">D</span></div><div class="t m0 x3 h3 y1f ff2 fs0 fc0 sc1 ls0 ws0">8.<span class="ff1">据库系统的核心是 。</span></div><div class="t m0 x3 h3 y20 ff2 fs0 fc0 sc1 ls0 ws0"> A<span class="_ _0"></span><span class="ff1">．数据库 <span class="_ _0"></span> </span>B<span class="_ _0"></span><span class="ff1">．<span class="fc1">数据库管理系<span class="_ _0"></span>统</span> <span class="_ _0"></span> </span>C<span class="ff1">．数<span class="_ _0"></span>据模型 <span class="_ _0"></span> </span>D<span class="ff1">．软件工具<span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> 答</span></div><div class="t m0 x3 h3 y21 ff1 fs0 fc0 sc1 ls0 ws0">案：<span class="ff2">B</span></div><div class="t m0 x3 h3 y22 ff2 fs0 fc0 sc1 ls0 ws0">9. <span class="ff1">下述关于数据库系统的正确叙述是 。</span></div></div></div><div class="pi" data-data='{"ctm":[1.611850,0.000000,0.000000,1.611850,0.000000,0.000000]}'></div></div>
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<div id="pf2" class="pf w0 h0" data-page-no="2"><div class="pc pc2 w0 h0"><img class="bi x0 y0 w1 h1" alt="" src="https://static.pudn.com/prod/directory_preview_static/6275e22f602a7856fe2a86a9/bg2.jpg"><div class="c x0 y1 w2 h2"><div class="t m0 x3 h3 y23 ff2 fs0 fc0 sc1 ls0 ws0"> A<span class="_ _0"></span><span class="ff1">．<span class="fc1">数据库<span class="_ _0"></span>系统减少了数<span class="_ _0"></span>据冗余<span class="_ _0"></span></span> <span class="_ _0"></span></span>B<span class="ff1">．数据库系<span class="_ _0"></span>统避免了一切<span class="_ _0"></span>冗余 <span class="_ _2"></span></span>C<span class="ff1">．数<span class="_ _0"></span>据库系统中数据的<span class="_ _0"></span>一致性是</span></div><div class="t m0 x3 h3 y24 ff1 fs0 fc0 sc1 ls0 ws0">指数据类型一致</div><div class="t m0 x3 h3 y25 ff2 fs0 fc0 sc1 ls0 ws0"> D<span class="ff1">．数据库系统比文件系统能管理更多的数据 答案：<span class="_ _0"></span></span>A</div><div class="t m0 x3 h3 y26 ff2 fs0 fc0 sc1 ls0 ws0">10. <span class="ff1">数将数据库的结构划分成多个层次，是为了提高数据库的 ① 和 ② 。</span></div><div class="t m0 x3 h3 y27 ff2 fs0 fc0 sc1 ls0 ws0"> ①A<span class="ff1">．数据独立性 </span>B<span class="ff1">．<span class="fc1">逻辑独立性</span> </span>C<span class="ff1">．管理规范性 </span>D<span class="ff1">．数据的共享</span></div><div class="t m0 x3 h3 y28 ff2 fs0 fc0 sc1 ls0 ws0"> <span class="_ _0"></span> ②A<span class="ff1">．<span class="_ _0"></span>数据独立<span class="_ _0"></span>性 <span class="_ _0"></span> <span class="_ _0"></span></span>B<span class="ff1">．<span class="fc1">物<span class="_ _0"></span>理独立<span class="_ _0"></span>性</span> <span class="_ _0"></span> <span class="_ _0"></span></span>C<span class="ff1">．逻<span class="_ _0"></span>辑独立性<span class="_ _0"></span> <span class="_ _0"></span> </span>D<span class="_ _0"></span><span class="ff1">．管理规<span class="_ _0"></span>范性 <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span>答案<span class="_ _2"></span>：</span></div><div class="t m0 x3 h3 y29 ff1 fs0 fc0 sc1 ls0 ws0">①<span class="_ _1"> </span><span class="ff2">B ②B</span></div><div class="t m0 x3 h3 y2a ff2 fs0 fc0 sc1 ls0 ws0">11. <span class="ff1">数据库</span>(DB)<span class="ff1">、数据库系统</span>(DB<span class="_ _5"></span>S)<span class="ff1">和数据库管理系统</span>(DBMS)<span class="ff1">三者之间的关系是 。</span></div><div class="t m0 x3 h3 y2b ff2 fs0 fc0 sc1 ls0 ws0"> <span class="_ _6"> </span> <span class="_ _3"></span> <span class="_ _3"></span> <span class="_ _2"></span>A<span class="_ _7"> </span><span class="ff1">．<span class="_ _3"></span></span><span class="fc1">DBS<span class="_"> </span><span class="ff1">包<span class="_ _4"></span>括<span class="_ _8"> </span></span>DB<span class="_"> </span><span class="ff1">和<span class="_"> </span></span>DBMS</span> <span class="_ _6"> </span> <span class="_ _3"></span> <span class="_ _3"> </span> <span class="_ _3"></span> <span class="_ _3"> </span> <span class="_ _7"> </span> <span class="_ _2"></span>B<span class="_ _7"> </span><span class="ff1">．<span class="_ _3"></span></span>DDMS<span class="_"> </span><span class="ff1">包<span class="_ _3"></span>括<span class="_"> </span></span>DB<span class="_"> </span><span class="ff1">和<span class="_"> </span></span>DBS<span class="_ _2"></span> <span class="_ _3"></span> <span class="_ _3"></span> <span class="_ _3"> </span> <span class="_ _4"></span>C<span class="_ _3"></span><span class="ff1">．<span class="_ _3"></span></span>DB<span class="_"> </span><span class="ff1">包<span class="_ _3"></span>括<span class="_ _8"> </span></span>DB<span class="_ _5"></span>S<span class="_"> </span><span class="ff1">和<span class="_"> </span></span>DBMS</div><div class="t m0 x3 h3 y2c ff2 fs0 fc0 sc1 ls0 ws0">D<span class="ff1">．</span>DBS<span class="_ _6"> </span><span class="ff1">就是<span class="_ _1"> </span></span>D<span class="_ _0"></span>B<span class="ff1">，也就是<span class="_ _1"> </span></span>DBMS</div><div class="t m0 x3 h3 y2d ff2 fs0 fc0 sc1 ls0 ws0"> <span class="ff1">答案：</span>A</div><div class="t m0 x3 h3 y2e ff2 fs0 fc1 sc1 ls0 ws0">12. <span class="ff1">在数据库中，产生数据不一致的根本原因是 。</span></div><div class="t m0 x3 h3 y2f ff2 fs0 fc1 sc1 ls0 ws0"> <span class="_ _0"></span> <span class="_ _0"></span> A<span class="_ _0"></span><span class="ff1">．<span class="_ _0"></span>数据<span class="_ _0"></span>存储<span class="_ _0"></span>量<span class="_ _0"></span>太大<span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span></span>B<span class="ff1">．<span class="_ _0"></span>没有<span class="_ _0"></span>严<span class="_ _0"></span>格保<span class="_ _0"></span>护数<span class="_ _0"></span>据<span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span></span>C<span class="ff1">．<span class="_ _0"></span>未对<span class="_ _0"></span>数<span class="_ _0"></span>据进<span class="_ _0"></span>行完<span class="_ _0"></span>整<span class="_ _0"></span>性控<span class="_ _0"></span>制 <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span></span>D<span class="_ _0"></span><span class="ff1">．<span class="_ _0"></span>数据<span class="_ _0"></span>冗<span class="_ _0"></span>余 <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span>答</span></div><div class="t m0 x3 h3 y30 ff1 fs0 fc1 sc1 ls0 ws0">案：<span class="ff2">D</span></div><div class="t m0 x3 h3 y31 ff2 fs0 fc0 sc1 ls0 ws0">13. <span class="ff1">数据库管理系统</span>(DBMS)<span class="ff1">是 <span class="_ _0"></span>。</span></div><div class="t m0 x3 h3 y32 ff2 fs0 fc0 sc1 ls0 ws0"> A<span class="ff1">．数学软件 <span class="_ _0"></span></span>B<span class="ff1">．应用软件 </span>C<span class="ff1">．计算机辅助设计 </span><span class="fc1">D<span class="ff1">．系统软件 <span class="fc0"> 答案：</span></span></span>D</div><div class="t m0 x3 h3 y33 ff2 fs0 fc0 sc1 ls0 ws0">14. <span class="ff1">数据库管理系统</span>(DBMS)<span class="ff1">的主要功能是 。</span></div><div class="t m0 x3 h3 y34 ff2 fs0 fc0 sc1 ls0 ws0"> A<span class="ff1">．修改数据库 </span>B<span class="ff1">．<span class="fc1">定义数据库 </span> </span>C<span class="ff1">．应用数据库 <span class="_ _0"></span></span>D<span class="ff1">．保护数据库 答案：</span>B</div><div class="t m0 x3 h3 y35 ff2 fs0 fc0 sc1 ls0 ws0">15. <span class="ff1">数据库系统的特点是 、数据独立、减少数据冗余、避免数据不一致和加强了数据保护。</span></div><div class="t m0 x3 h3 y36 ff2 fs0 fc0 sc1 ls0 ws0"> A<span class="ff1">．<span class="fc1">数据共享 </span> </span>B<span class="ff1">．数据存储 </span>C<span class="ff1">．数据应用 </span>D<span class="_ _0"></span><span class="ff1">．数据保密 答案：</span>A</div><div class="t m0 x3 h3 y37 ff2 fs0 fc1 sc1 ls0 ws0">16<span class="_ _1"> </span><span class="ff1">据库系统的最大特点是 。</span></div><div class="t m0 x3 h3 y38 ff2 fs0 fc1 sc1 ls0 ws0"> A<span class="_ _0"></span><span class="ff1">．数据的<span class="_ _0"></span>三级抽象和二<span class="_ _0"></span>级独立性 <span class="_ _0"></span> <span class="_ _4"></span></span>B<span class="ff1">．数据共<span class="_ _0"></span>享性 <span class="_ _2"></span></span>C<span class="ff1">．数据的结<span class="_ _0"></span>构化 <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _3"></span></span>D<span class="ff1">．数据独</span></div><div class="t m0 x3 h3 y39 ff1 fs0 fc1 sc1 ls0 ws0">立性 答案：<span class="ff2">A</span></div><div class="t m0 x3 h3 y3a ff2 fs0 fc0 sc1 ls0 ws0">17. <span class="_ _1"> </span><span class="ff1">数<span class="_ _3"></span>据<span class="_ _4"></span>库<span class="_ _3"></span>管<span class="_ _4"></span>理<span class="_ _3"></span>系<span class="_ _4"></span>统<span class="_ _3"></span>能<span class="_ _4"></span>实<span class="_ _3"></span>现<span class="_ _3"></span>对<span class="_ _4"></span>数<span class="_ _3"></span>据<span class="_ _4"></span>库<span class="_ _3"></span>中<span class="_ _4"></span>数<span class="_ _3"></span>据<span class="_ _3"></span>的<span class="_ _4"></span>查<span class="_ _3"></span>询<span class="_ _4"></span>、<span class="_ _3"></span>插<span class="_ _4"></span>入<span class="_ _3"></span>、<span class="_ _4"></span>修<span class="_ _3"></span>改<span class="_ _3"></span>和<span class="_ _4"></span>删<span class="_ _3"></span>除<span class="_ _4"></span>等<span class="_ _3"></span>操<span class="_ _3"></span>作<span class="_ _4"></span>，<span class="_ _3"></span>这<span class="_ _4"></span>种<span class="_ _3"></span>功<span class="_ _4"></span>能<span class="_ _3"></span>称<span class="_ _4"></span>为</span></div><div class="t m0 x3 h3 y3b ff1 fs0 fc0 sc1 ls0 ws0">。</div><div class="t m0 x3 h3 y3c ff2 fs0 fc0 sc1 ls0 ws0"> A<span class="ff1">．数据定义功能 </span>B<span class="ff1">．数据管理功能 </span>C<span class="ff1">．<span class="fc1">数据操纵功能</span> </span>D<span class="_ _0"></span><span class="ff1">．数据控制功能 答案：</span>C</div><div class="t m0 x3 h3 y3d ff2 fs0 fc0 sc1 ls0 ws0">18. <span class="ff1">数据库管理系统是 。</span></div><div class="t m0 x3 h3 y3e ff2 fs0 fc0 sc1 ls0 ws0"> <span class="_ _0"></span> <span class="_ _0"></span> A<span class="_ _0"></span><span class="ff1">．<span class="_ _0"></span>操作<span class="_ _0"></span>系统<span class="_ _0"></span>的<span class="_ _0"></span>一部<span class="_ _0"></span>分 <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span></span>B<span class="_ _0"></span><span class="ff1">．<span class="_ _0"></span><span class="fc1">在操<span class="_ _0"></span>作系<span class="_ _0"></span>统<span class="_ _0"></span>支持<span class="_ _0"></span>下的<span class="_ _0"></span>系<span class="_ _0"></span>统软<span class="_ _0"></span>件<span class="_ _0"></span></span> <span class="_ _0"></span> <span class="_ _0"></span> </span>C<span class="_ _0"></span><span class="ff1">．<span class="_ _0"></span>一种<span class="_ _0"></span>编译<span class="_ _0"></span>程<span class="_ _0"></span>序 <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span></span>D<span class="ff1">．<span class="_ _0"></span>一<span class="_ _0"></span>种操<span class="_ _0"></span>作</span></div><div class="t m0 x3 h3 y3f ff1 fs0 fc0 sc1 ls0 ws0">系统 答案：<span class="ff2">B</span></div><div class="t m0 x3 h3 y40 ff2 fs0 fc0 sc1 ls0 ws0">19.<span class="ff1">据库的三级模式结构中，<span class="fc1">描述数据库中全体数据的全局逻辑结构和特征的是</span>（）</span></div><div class="t m0 x3 h3 y41 ff2 fs0 fc0 sc1 ls0 ws0"> A<span class="ff1">．外模式 </span>B<span class="ff1">．内模式 </span>C<span class="ff1">．存储模式 </span>D<span class="_ _0"></span><span class="ff1 fc1">．模式 <span class="fc0"> 答案：</span></span>D</div><div class="t m0 x3 h3 y42 ff2 fs0 fc1 sc1 ls0 ws0">20<span class="_ _1"> </span><span class="ff1">据库系统的数据独立性是指 <span class="_ _9"></span> <span class="_ _a"> </span> <span class="ff2">B <span class="_ _0"></span> <span class="_ _b"></span><span class="ff1"> <span class="_ _c"> </span> 。 </span></span></span></div><div class="t m0 x4 h3 y43 ff2 fs0 fc0 sc1 ls0 ws0">A<span class="ff1">．不会因为数据的变</span></div><div class="t m0 x4 h3 y44 ff1 fs0 fc0 sc1 ls0 ws0">化而影响应用程序 <span class="ff2 fc1">B<span class="ff1">．不会因为系统数据存储结构与数据逻辑结构的变化而影响应用程序</span></span></div></div></div><div class="pi" data-data='{"ctm":[1.611850,0.000000,0.000000,1.611850,0.000000,0.000000]}'></div></div>
<div id="pf3" class="pf w0 h0" data-page-no="3"><div class="pc pc3 w0 h0"><img class="bi x0 y0 w1 h1" alt="" src="https://static.pudn.com/prod/directory_preview_static/6275e22f602a7856fe2a86a9/bg3.jpg"><div class="c x0 y1 w2 h2"><div class="t m0 x3 h3 y23 ff2 fs0 fc0 sc1 ls0 ws0"> <span class="_ _0"></span> <span class="_ _0"></span> C<span class="_ _0"></span><span class="ff1">．<span class="_ _0"></span>不<span class="_ _0"></span>会因<span class="_ _0"></span>为存<span class="_ _0"></span>储<span class="_ _0"></span>策略<span class="_ _0"></span>的变<span class="_ _0"></span>化<span class="_ _0"></span>而影<span class="_ _0"></span>响存<span class="_ _0"></span>储<span class="_ _0"></span>结构<span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _4"></span></span>D<span class="_ _0"></span><span class="ff1">．<span class="_ _0"></span>不会<span class="_ _0"></span>因为<span class="_ _0"></span>某<span class="_ _0"></span>些存<span class="_ _0"></span>储结<span class="_ _0"></span>构<span class="_ _0"></span>的变<span class="_ _0"></span>化而<span class="_ _0"></span>影<span class="_ _0"></span>响其<span class="_ _0"></span>他的<span class="_ _0"></span>存</span></div><div class="t m0 x3 h3 y24 ff1 fs0 fc0 sc1 ls0 ws0">储结构 答案：<span class="ff2">B</span></div><div class="t m0 x3 h3 y25 ff2 fs0 fc0 sc1 ls0 ws0">21.<span class="ff1">信息世界中的术语，与之对应的数据库术语为 。</span></div><div class="t m0 x3 h3 y26 ff2 fs0 fc0 sc1 ls0 ws0"> A<span class="ff1">．文件 </span>B<span class="ff1">．数据库 </span>C<span class="ff1">．字段 <span class="fc1"> <span class="ff2">D<span class="_ _0"></span></span>．记录 </span> 答案：</span>D</div><div class="t m0 x3 h3 y27 ff2 fs0 fc0 sc1 ls0 ws0">22<span class="_ _1"> </span><span class="ff1">次型、网状型和关系型数据库划分原则是 。</span></div><div class="t m0 x3 h3 y28 ff2 fs0 fc0 sc1 ls0 ws0"> A<span class="ff1">．记录长度 </span>B<span class="ff1">．文件的大小 </span>C<span class="ff1">．联系的复杂程度 <span class="_ _0"></span></span>D<span class="ff1">．<span class="fc1">数据之间的联系 </span> 答案：</span>D</div><div class="t m0 x3 h3 y29 ff2 fs0 fc0 sc1 ls0 ws0">23.<span class="ff1">传统的数据模型分类，数据库系统可以分为三种类型 。</span></div><div class="t m0 x3 h3 y2a ff2 fs0 fc0 sc1 ls0 ws0"> A<span class="ff1">．大型、中型和小型 <span class="_ _2"></span></span>B<span class="ff1">．西文、中文和兼容 <span class="_ _2"></span></span>C<span class="ff1">．<span class="fc1">层次、网状和关系 <span class="_ _0"></span></span> </span>D<span class="ff1">．数据、图<span class="ff3">形</span>和多<span class="ff3">媒</span>体</span></div><div class="t m0 x3 h3 y2b ff1 fs0 fc0 sc1 ls0 ws0">答案：<span class="ff2">C</span></div><div class="t m0 x3 h3 y2c ff2 fs0 fc0 sc1 ls0 ws0">24. <span class="ff1">层次模型<span class="fc1">不能</span><span class="ff3">直接表示</span> 。</span></div><div class="t m0 x5 h3 y2d ff2 fs0 fc0 sc1 ls0 ws0">A<span class="ff1">． </span>1 <span class="_ _0"></span><span class="ff1">：</span>1<span class="_ _1"> </span><span class="ff1">关系 <span class="_ _0"></span> <span class="_ _0"></span></span>B<span class="ff1">．</span>1 <span class="ff1">：</span>m<span class="_ _d"> </span><span class="ff1">关系 <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span></span>C<span class="_ _0"></span><span class="ff1">．<span class="fc1"> <span class="ff2">m </span>：<span class="ff2">n<span class="_ _d"> </span></span>关系 </span> <span class="_ _0"></span> </span>D<span class="ff1">．<span class="_ _0"></span></span>1 <span class="ff1">：</span>1<span class="_ _1"> </span><span class="ff1">和<span class="_ _1"> </span></span>1<span class="_ _0"></span> <span class="ff1">：</span>m<span class="_ _1"> </span><span class="ff1">关系<span class="_ _0"></span> 答</span></div><div class="t m0 x5 h3 y2e ff1 fs0 fc0 sc1 ls0 ws0">案：<span class="ff2">C</span></div><div class="t m0 x3 h3 y2f ff2 fs0 fc0 sc1 ls0 ws0">25. <span class="ff1">数据库技术的<span class="ff3">奠</span>基人之一<span class="_ _1"> </span></span><span class="fc1">E.F<span class="ff1">．</span>Codd<span class="_ _1"> </span></span><span class="ff3">从<span class="_ _1"> </span></span>1970<span class="_ _1"> </span><span class="ff3">年起<span class="ff1">发</span>表<span class="ff1">过多</span>篇<span class="ff1">论文，主要论述的是 <span class="_ _0"></span>。</span></span></div><div class="t m0 x3 h3 y30 ff2 fs0 fc0 sc1 ls0 ws0"> <span class="_ _d"> </span> <span class="_ _7"> </span> <span class="_ _6"> </span> <span class="_ _4"></span>A<span class="_ _6"> </span><span class="ff1">．<span class="_ _6"> </span>层<span class="_ _7"> </span>次<span class="_ _6"> </span>数<span class="_ _6"> </span>据<span class="_ _7"> </span>模<span class="_ _6"> </span>型<span class="_ _7"> </span> <span class="_ _6"> </span> <span class="_ _7"> </span> <span class="_ _6"> </span> <span class="_ _1"> </span></span>B<span class="_ _7"> </span><span class="ff1">．<span class="_ _6"> </span>网<span class="_ _7"> </span>状<span class="_ _6"> </span>数<span class="_ _7"> </span>据<span class="_ _6"> </span>模<span class="_ _6"> </span>型<span class="_ _7"> </span> <span class="_ _6"> </span> <span class="_ _7"> </span> <span class="_ _1"> </span></span>C<span class="_ _7"> </span><span class="ff1">．<span class="_ _6"> </span><span class="fc1">关<span class="_ _6"> </span>系<span class="_ _7"> </span>数<span class="_ _6"> </span>据<span class="_ _7"> </span>模<span class="_ _6"> </span>型<span class="_ _6"> </span></span> <span class="_ _6"> </span> <span class="_ _7"> </span> <span class="_ _6"> </span> <span class="_ _6"> </span></span>D<span class="_ _7"> </span><span class="ff1">．<span class="_ _6"> </span><span class="ff3">面<span class="_ _6"> </span>向<span class="_ _7"> </span></span>对<span class="_ _6"> </span>象<span class="_ _7"> </span>数<span class="_ _6"> </span>据<span class="_ _7"> </span>模<span class="_ _6"> </span>型</span></div><div class="t m0 x3 h3 y31 ff1 fs0 fc0 sc1 ls0 ws0">答案：<span class="ff2">C</span></div><div class="t m0 x3 h3 y32 ff1 fs0 fc0 sc1 ls0 ws0">二、<span class="ff3">填空</span>题</div><div class="t m0 x3 h3 y33 ff2 fs0 fc0 sc1 ls0 ws0">1. <span class="ff1">数据<span class="_ _0"></span>管理技<span class="_ _0"></span>术经历了<span class="_ _0"></span> <span class="_ _0"></span>人工管理<span class="_ _0"></span> 、<span class="_ _0"></span> 文件系<span class="_ _0"></span>统 <span class="_ _0"></span> <span class="_ _0"></span>和 <span class="_ _0"></span>数据库系<span class="_ _0"></span>统 三<span class="_ _0"></span>个阶段<span class="_ _0"></span>。 <span class="_ _0"></span> 答案<span class="_ _0"></span>：①人工<span class="_ _0"></span>管理 <span class="_ _0"></span> ②</span></div><div class="t m0 x3 h3 y34 ff1 fs0 fc0 sc1 ls0 ws0">文件系统 ②数据库系统</div><div class="t m0 x3 h3 y35 ff2 fs0 fc0 sc1 ls0 ws0">2. <span class="ff1 fc1">数据库是长<span class="ff3">期</span>存储在计算机内、有 <span class="ff3">组织</span>的、可共享的数据集合<span class="fc0">。 答案：①<span class="ff3">组织</span> ②共享</span></span></div><div class="t m0 x3 h3 y36 ff2 fs0 fc0 sc1 ls0 ws0">3<span class="ff1">．</span><span class="fc1">DBMS<span class="_ _1"> </span><span class="ff1">是指 <span class="ff3">它</span>是<span class="ff3">位</span>于 用户 <span class="_ _0"></span>和 <span class="ff3">③</span> 之间的一层管理软件<span class="_ _0"></span><span class="fc0">。 答案：①数据库管理系统 ②用户</span></span></span></div><div class="t m0 x3 h3 y37 ff3 fs0 fc0 sc1 ls0 ws0">③<span class="ff1">操作系统</span></div><div class="t m0 x3 h3 y38 ff2 fs0 fc0 sc1 ls0 ws0">4. <span class="ff1">数据<span class="_ _0"></span>库管理<span class="_ _0"></span>系统的<span class="_ _0"></span><span class="fc1">主要功<span class="_ _0"></span>能</span>有<span class="fc1">数<span class="_ _0"></span>据定义功<span class="_ _0"></span>能 <span class="_ _0"></span></span> 、<span class="fc1">数据<span class="_ _0"></span>操纵功能<span class="_ _0"></span> <span class="_ _0"></span></span>、<span class="fc1">数据<span class="_ _0"></span>库的<span class="ff3">运<span class="_ _0"></span></span>行管理<span class="_ _0"></span></span>和<span class="fc1">数据库<span class="_ _0"></span>的<span class="ff3">建</span>立</span></span></div><div class="t m0 x3 h3 y39 ff1 fs0 fc1 sc1 ls0 ws0">以及<span class="ff3">维</span>护<span class="fc0">等<span class="_ _1"> </span><span class="ff2">4<span class="_ _1"> </span></span>个<span class="ff3">方面</span>。</span></div><div class="t m0 x5 h3 y3a ff1 fs0 fc0 sc1 ls0 ws0">答案：①数据定义功能 ②数据操纵功能</div><div class="t m0 x3 h3 y3b ff2 fs0 fc0 sc1 ls0 ws0">5. <span class="_ _0"></span><span class="ff1 fc1">数据独立<span class="_ _0"></span>性<span class="_ _0"></span></span><span class="ff3">又<span class="ff1">可分<span class="_ _0"></span>为<span class="fc1">逻<span class="_ _0"></span>辑数据独<span class="_ _0"></span>立性<span class="_ _0"></span></span> <span class="_ _0"></span> <span class="_ _0"></span>和 <span class="_ _0"></span><span class="fc1">物理数<span class="_ _0"></span>据独立性<span class="_ _2"></span></span>。 <span class="_ _0"></span> 答案：<span class="_ _0"></span>①逻辑数<span class="_ _0"></span>据独立<span class="_ _0"></span>性 <span class="_ _0"></span> ②物理<span class="_ _0"></span>数</span></span></div><div class="t m0 x3 h3 y3c ff1 fs0 fc0 sc1 ls0 ws0">据独立性</div><div class="t m0 x3 h3 y3d ff2 fs0 fc0 sc1 ls0 ws0">6. <span class="_ _0"></span><span class="ff3">当<span class="_ _0"></span><span class="ff1">数<span class="_ _0"></span>据<span class="_ _0"></span>的<span class="_ _0"></span><span class="fc1">物<span class="_ _0"></span>理存<span class="_ _0"></span>储<span class="_ _0"></span>改<span class="_ _0"></span>变<span class="_ _0"></span></span>了<span class="_ _0"></span>，<span class="_ _0"></span><span class="fc1">应用<span class="_ _0"></span>程<span class="_ _0"></span>序<span class="_ _0"></span>不变<span class="_ _2"></span></span>，<span class="_ _0"></span>而</span>由<span class="_ _d"> </span></span>D<span class="_ _0"></span>BMS<span class="_ _1"> </span><span class="ff3">处<span class="_ _0"></span><span class="ff1">理<span class="_ _0"></span>这<span class="_ _0"></span>种改<span class="_ _0"></span>变<span class="_ _0"></span>，<span class="_ _0"></span>这是<span class="_ _0"></span>指<span class="_ _0"></span>数<span class="_ _0"></span>据的<span class="_ _4"></span> <span class="_ _e"></span> <span class="_ _f"></span> <span class="fc1">物<span class="_ _0"></span>理独<span class="_ _0"></span>立<span class="_ _0"></span>性<span class="_ _10"></span> <span class="_ _11"> </span> </span></span></span></div><div class="t m0 x3 h3 y3e ff1 fs0 fc0 sc1 ls0 ws0">。 答案：物理独立性</div><div class="t m0 x3 h3 y3f ff2 fs0 fc0 sc1 ls0 ws0">7. <span class="_ _2"></span><span class="ff1 fc1">数<span class="_ _0"></span>据<span class="_ _0"></span>模<span class="_ _0"></span>型<span class="_ _0"></span><span class="fc0">是<span class="_ _0"></span><span class="ff3">由<span class="_ _0"></span></span></span>数<span class="_ _0"></span>据<span class="_ _0"></span>结<span class="_ _0"></span>构<span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _2"></span>、<span class="_ _0"></span>数<span class="_ _0"></span>据<span class="_ _0"></span>操作<span class="_ _2"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _2"></span>和<span class="_ _0"></span>完<span class="_ _0"></span>整<span class="_ _0"></span>性<span class="_ _0"></span><span class="ff3">约<span class="_ _0"></span>束<span class="_ _0"></span></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _2"></span>三<span class="_ _0"></span>部<span class="_ _0"></span>分<span class="_ _0"></span><span class="ff3">组<span class="_ _0"></span></span>成<span class="_ _0"></span><span class="fc0">的<span class="_ _0"></span>。<span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span>答<span class="_ _0"></span>案<span class="_ _0"></span>：①<span class="_ _0"></span>数<span class="_ _0"></span>据<span class="_ _0"></span>结<span class="_ _0"></span>构</span></span></div><div class="t m0 x3 h3 y40 ff1 fs0 fc0 sc1 ls0 ws0">②数据操作 <span class="ff3">③</span>完整性<span class="ff3">约束</span></div><div class="t m0 x3 h3 y41 ff2 fs0 fc0 sc1 ls0 ws0">8. <span class="_ _12"></span> <span class="_ _e"></span> <span class="_ _0"></span><span class="ff1 fc1">数<span class="_ _0"></span>据<span class="_ _0"></span>结<span class="_ _0"></span>构<span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _13"></span><span class="ff2"> <span class="_ _14"> </span> <span class="ff1">是<span class="_ _0"></span>对<span class="_ _0"></span>数<span class="_ _0"></span>据<span class="_ _0"></span>系<span class="_ _0"></span>统<span class="_ _0"></span>的<span class="_ _0"></span><span class="ff3">静<span class="_ _0"></span>态<span class="_ _0"></span></span>特<span class="_ _0"></span>性<span class="_ _0"></span>的<span class="_ _0"></span>描述<span class="_ _2"></span><span class="fc0">，<span class="_ _0"></span></span>数<span class="_ _0"></span>据<span class="_ _0"></span>操<span class="_ _0"></span>作<span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _2"></span>是<span class="_ _0"></span>对数<span class="_ _0"></span>据<span class="_ _0"></span>库<span class="_ _0"></span>系<span class="_ _0"></span>统<span class="_ _0"></span>的<span class="_ _0"></span><span class="ff3">动<span class="_ _0"></span>态<span class="_ _0"></span></span>特<span class="_ _0"></span>性<span class="_ _0"></span>的<span class="_ _0"></span>描<span class="_ _0"></span>述<span class="_ _0"></span><span class="fc0">。</span></span></span></span></div><div class="t m0 x3 h3 y42 ff1 fs0 fc0 sc1 ls0 ws0">答案：①数据结构 ②数据操作</div><div class="t m0 x3 h3 y43 ff2 fs0 fc0 sc1 ls0 ws0">9. <span class="_ _2"></span><span class="ff1 fc1">数<span class="_ _0"></span>据<span class="_ _0"></span>库<span class="_ _0"></span>体<span class="_ _0"></span>系<span class="_ _0"></span>结<span class="_ _0"></span>构<span class="_ _2"></span><span class="ff3">按<span class="_ _0"></span>照<span class="_ _0"></span></span> <span class="_ _0"></span>模<span class="_ _0"></span>式<span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _2"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _2"></span>、<span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span>外<span class="_ _0"></span>模<span class="_ _0"></span>式<span class="_ _0"></span> <span class="_ _2"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _2"></span>和<span class="_ _0"></span> <span class="_ _0"></span>内<span class="_ _0"></span>模<span class="_ _0"></span>式<span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _2"></span>三<span class="_ _0"></span>级<span class="_ _0"></span>结<span class="_ _0"></span>构<span class="_ _0"></span>进<span class="_ _0"></span>行<span class="_ _2"></span><span class="ff3">组<span class="_ _0"></span>织<span class="_ _0"></span></span><span class="fc0">。<span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _2"></span> <span class="_ _0"></span> <span class="_ _0"></span>答<span class="_ _0"></span>案<span class="_ _0"></span>：<span class="_ _0"></span>①<span class="_ _0"></span>模<span class="_ _0"></span>式</span></span></div><div class="t m0 x3 h3 y44 ff1 fs0 fc0 sc1 ls0 ws0">②外模式 <span class="ff3">③</span>内模式</div></div></div><div class="pi" data-data='{"ctm":[1.611850,0.000000,0.000000,1.611850,0.000000,0.000000]}'></div></div>
<div id="pf4" class="pf w0 h0" data-page-no="4"><div class="pc pc4 w0 h0"><img class="bi x0 y0 w1 h1" alt="" src="https://static.pudn.com/prod/directory_preview_static/6275e22f602a7856fe2a86a9/bg4.jpg"><div class="c x0 y1 w2 h2"><div class="t m0 x3 h3 y23 ff2 fs0 fc0 sc1 ls0 ws0">10. <span class="_ _0"></span><span class="ff1">实<span class="_ _0"></span>体<span class="_ _0"></span>之间<span class="_ _0"></span>的<span class="_ _0"></span>联<span class="_ _0"></span>系可<span class="_ _0"></span>抽<span class="_ _0"></span>象<span class="_ _0"></span>为三<span class="_ _0"></span>类<span class="_ _0"></span>，<span class="_ _0"></span><span class="ff3">它<span class="_ _0"></span>们<span class="_ _0"></span></span>是<span class="_ _0"></span> </span>1∶<span class="_ _0"></span>1 <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _2"></span><span class="ff1">、<span class="_ _0"></span> <span class="_ _0"></span> </span>1∶m <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _2"></span><span class="ff1">和<span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span></span>m∶n <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _2"></span> <span class="_ _0"></span><span class="ff1">。 <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span>答案<span class="_ _0"></span>：<span class="_ _0"></span>①<span class="_ _d"> </span></span>1∶1</div><div class="t m0 x3 h4 y45 ff2 fs0 fc0 sc1 ls0 ws0">②1∶m ②m∶n</div><div class="t m0 x3 h3 y46 ff2 fs0 fc0 sc1 ls0 ws0">11<span class="ff1">．<span class="fc1">数据冗余</span>可能<span class="ff3 fc1">导<span class="ff1">致的</span>问<span class="ff1">题<span class="_ _0"></span></span></span>有 ① <span class="_ _2"></span>和 ② <span class="_ _0"></span>。 答案：①<span class="_ _2"></span><span class="ff3 fc1">浪费<span class="ff1">存储</span>空<span class="ff1">间及修改</span>麻烦<span class="_ _0"></span></span> ②<span class="_ _0"></span><span class="ff3 fc1">潜<span class="ff1">在</span></span></span></div><div class="t m0 x3 h3 y47 ff1 fs0 fc1 sc1 ls0 ws0">的数据不一致性</div><div class="t m0 x3 h3 y48 ff1 fs0 fc0 sc1 ls0 ws0">三：<span class="ff3">简</span>答题：</div><div class="t m0 x3 h3 y49 ff2 fs0 fc0 sc1 ls0 ws0">1. <span class="ff3 fc2">什么<span class="ff1">是数据库<span class="ff2">?</span></span></span></div><div class="t m0 x5 h3 y4a ff1 fs0 fc0 sc1 ls0 ws0">答：<span class="fc1">数据库</span>是<span class="fc1">长<span class="ff3">期</span>存储<span class="_ _0"></span></span>在<span class="fc1">计算机内</span>、<span class="fc1">有<span class="ff3">组织</span>的<span class="_ _0"></span></span>、<span class="fc1">可共享</span>的<span class="fc1">数据集合</span>。数据库是<span class="ff3">按</span>某种数据模型进行</div><div class="t m0 x3 h3 y4b ff3 fs0 fc0 sc1 ls0 ws0">组织<span class="_ _0"></span><span class="ff1">的<span class="_ _0"></span>、存<span class="_ _0"></span></span>放<span class="ff1">在<span class="_ _2"></span><span class="fc1">外<span class="_ _0"></span>存储<span class="_ _0"></span>器<span class="_ _0"></span></span>上<span class="_ _0"></span>，</span>且<span class="_ _0"></span><span class="ff1">可</span>被<span class="_ _0"></span><span class="ff1">多<span class="_ _0"></span>个<span class="_ _0"></span><span class="fc1">用<span class="_ _0"></span>户<span class="_ _0"></span>同<span class="ff3">时<span class="_ _0"></span></span></span>使<span class="_ _0"></span>用<span class="_ _0"></span>。因<span class="_ _0"></span></span>此<span class="_ _0"></span><span class="ff1">，数<span class="_ _0"></span>据库<span class="_ _0"></span>具<span class="_ _0"></span>有<span class="_ _2"></span></span><span class="fc1">较<span class="_ _0"></span><span class="ff1">小的<span class="_ _0"></span>冗余<span class="_ _0"></span>度<span class="_ _0"></span><span class="fc0">，<span class="_ _0"></span></span></span>较<span class="_ _0"></span><span class="ff1">高的<span class="_ _0"></span>数</span></span></div><div class="t m0 x3 h3 y4c ff1 fs0 fc1 sc1 ls0 ws0">据独立性和易扩展性<span class="fc0">。</span></div><div class="t m0 x3 h3 y4d ff2 fs0 fc0 sc1 ls0 ws0">2. <span class="ff3 fc2">什么<span class="ff1">是数据库的数据独立性<span class="ff2">?</span></span></span></div><div class="t m0 x3 h3 y4e ff2 fs0 fc0 sc1 ls0 ws0"> <span class="_ _0"></span> <span class="_ _0"></span><span class="ff1">答：<span class="_ _0"></span><span class="fc1">数据<span class="_ _0"></span>独立<span class="_ _0"></span>性</span><span class="ff3">表<span class="_ _0"></span>示</span><span class="fc1">应<span class="_ _0"></span>用程<span class="_ _0"></span>序</span>与<span class="_ _0"></span>数据<span class="_ _0"></span>库中<span class="_ _0"></span><span class="fc1">存储的<span class="_ _0"></span>数据<span class="_ _0"></span>不存在<span class="_ _0"></span><span class="ff3">依<span class="_ _0"></span>赖</span>关<span class="_ _0"></span>系</span>，<span class="_ _0"></span>包括<span class="_ _0"></span><span class="fc1">逻辑<span class="_ _0"></span>数据<span class="_ _0"></span>独立性<span class="_ _0"></span></span>和<span class="_ _0"></span><span class="fc1">物理</span></span></div><div class="t m0 x3 h3 y4f ff1 fs0 fc1 sc1 ls0 ws0">数据独立性<span class="fc0">。</span></div><div class="t m0 x3 h3 y50 ff2 fs0 fc0 sc1 ls0 ws0"> <span class="ff1 fc1">逻辑数据独立性<span class="fc0">是指</span>局部逻辑数据结构</span>(<span class="ff1">外<span class="ff3">视</span>图<span class="ff3">即</span>用户的逻辑文件<span class="_ _0"></span></span>)<span class="ff1">与<span class="fc1">全局逻辑数据结构</span></span>(<span class="ff1">概念<span class="ff3">视</span>图</span>)<span class="ff1">之</span></div><div class="t m0 x3 h3 y51 ff1 fs0 fc0 sc1 ls0 ws0">间的<span class="_ _0"></span>独立性<span class="_ _0"></span>。<span class="_ _0"></span><span class="ff3">当<span class="_ _0"></span></span><span class="fc1">数据<span class="_ _0"></span>库的<span class="_ _0"></span>全局逻<span class="_ _0"></span>辑数据<span class="_ _0"></span>结构<span class="_ _4"></span></span><span class="ff2">(<span class="_ _0"></span></span>概念<span class="_ _0"></span><span class="ff3">视</span>图<span class="_ _0"></span><span class="ff2 fc1">)<span class="ff1">发<span class="_ _0"></span>生变<span class="_ _0"></span>化<span class="_ _0"></span></span><span class="fc0">(</span></span>数<span class="_ _0"></span>据定义<span class="_ _0"></span>的修<span class="_ _0"></span>改、<span class="_ _0"></span>数据<span class="_ _0"></span>之间联<span class="_ _0"></span>系的<span class="_ _0"></span>变</div><div class="t m0 x3 h3 y52 ff1 fs0 fc0 sc1 ls0 ws0">更或<span class="ff3">增</span>加<span class="ff3">新</span>的数据类型等<span class="ff2">)<span class="ff3 fc1">时</span></span>，<span class="ff3">它</span><span class="fc1">不影响某些局部的逻辑结构的性<span class="ff3">质</span></span>，<span class="fc1">应用程序不<span class="ff3">必</span>修改。</span></div><div class="t m0 x3 h3 y53 ff2 fs0 fc0 sc1 ls0 ws0"> <span class="_ _0"></span> <span class="ff1 fc1">物理<span class="_ _0"></span>数据独<span class="_ _0"></span>立性<span class="_ _0"></span><span class="fc0">是指</span>数<span class="_ _0"></span>据的存储<span class="_ _0"></span>结构与存<span class="_ _0"></span><span class="ff3">取方<span class="_ _0"></span>法</span></span>(<span class="ff1">内<span class="_ _0"></span><span class="ff3">视</span>图</span>)<span class="_ _0"></span><span class="ff1 fc1">改变<span class="ff3">时<span class="_ _0"></span></span><span class="fc0">，对数<span class="_ _0"></span>据库的全<span class="_ _0"></span>局逻辑结<span class="_ _0"></span>构<span class="_ _0"></span></span></span>(<span class="ff1">概念<span class="_ _0"></span><span class="ff3">视</span></span></div><div class="t m0 x3 h3 y54 ff1 fs0 fc0 sc1 ls0 ws0">图<span class="ff2">)</span>和应用程序<span class="fc1">不<span class="ff3">必</span>作修改的一种特性</span>，也就是<span class="ff3">说</span>，<span class="fc1">数据库数据的存储结构与存<span class="ff3">取方法</span>独立</span>。</div><div class="t m0 x3 h3 y55 ff2 fs0 fc0 sc1 ls0 ws0">3.<span class="fc2"> <span class="ff3">什么<span class="ff1">是数据库管理系统</span></span>?</span></div><div class="t m0 x3 h3 y56 ff2 fs0 fc0 sc1 ls0 ws0"> <span class="ff1">答：数据库管理系统</span>(DBMS)<span class="ff1">是<span class="fc1">操纵和管理数据库的一<span class="ff3">组</span>软件</span>，<span class="ff3">它</span>是<span class="fc1">数据库系统<span class="ff2">(DBS)</span>的<span class="ff3">重</span>要<span class="ff3">组</span>成部</span></span></div><div class="t m0 x3 h3 y57 ff1 fs0 fc1 sc1 ls0 ws0">分<span class="fc0">。不<span class="_ _0"></span>同的数据<span class="_ _0"></span>库系统<span class="_ _0"></span><span class="ff3">都配</span>有<span class="_ _0"></span><span class="ff3">各自</span>的<span class="_ _d"> </span><span class="ff2">DBMS<span class="_ _0"></span></span>，而不同<span class="_ _0"></span>的<span class="_ _d"> </span><span class="ff2">DBMS<span class="_ _1"> </span><span class="ff3">各</span></span>支持<span class="_ _0"></span>一种数据<span class="_ _0"></span>库模型，<span class="_ _0"></span><span class="ff3">虽然<span class="_ _0"></span>它们</span>的<span class="_ _0"></span>功</span></div><div class="t m0 x3 h3 y58 ff1 fs0 fc0 sc1 ls0 ws0">能强<span class="ff3">弱</span>不同，<span class="ff3">但</span>大多数<span class="_ _1"> </span><span class="ff2">DBMS<span class="_ _1"> </span></span>的构成相同，功能相<span class="ff3">似</span>。</div><div class="t m0 x3 h3 y59 ff2 fs0 fc0 sc1 ls0 ws0"> <span class="_ _0"></span> <span class="_ _0"></span><span class="ff1">一<span class="ff3">般说来<span class="_ _0"></span></span>，</span><span class="fc1">D<span class="_ _0"></span>BMS<span class="_ _1"> </span><span class="ff1">具有<span class="_ _0"></span><span class="fc3">定义</span>、<span class="_ _0"></span><span class="ff3">建</span>立、<span class="_ _0"></span><span class="ff3">维</span>护和使<span class="_ _0"></span>用数据库<span class="_ _0"></span>的功能<span class="_ _2"></span><span class="fc0">，<span class="ff3">它<span class="_ _0"></span>通常由<span class="_ _0"></span></span>三部分构<span class="_ _0"></span>成<span class="_ _0"></span></span>：数据<span class="_ _0"></span>描述语</span></span></div><div class="t m0 x3 h3 y5a ff1 fs0 fc1 sc1 ls0 ws0">言及其<span class="ff3">翻</span>译程序、数据操纵语言及其<span class="ff3">处</span>理程序和数据库管理<span class="fc0">的<span class="ff3">例</span>行程序。</span></div><div class="t m0 x3 h3 y5b ff2 fs0 fc0 sc1 ls0 ws0">4. <span class="ff3 fc2">什么<span class="ff1">是数据字</span>典</span>?<span class="ff1">数据字<span class="ff3">典</span><span class="fc2">包<span class="ff3">含哪</span>些基本内容</span></span>?</div><div class="t m0 x5 h3 y5c ff1 fs0 fc0 sc1 ls0 ws0">答<span class="fc1">：数据字<span class="ff3">典</span>是数据库系统中<span class="ff3">各</span>种描述信息和控制信息的集合<span class="_ _4"></span></span>，<span class="ff3">它</span>是<span class="fc1">数据库设计与管理的有<span class="ff3">力</span>工具<span class="_ _2"></span></span>，</div><div class="t m0 x3 h3 y5d ff1 fs0 fc0 sc1 ls0 ws0">是<span class="fc1">进<span class="_ _0"></span>行<span class="_ _0"></span><span class="ff3">详细<span class="_ _0"></span></span>数据<span class="_ _0"></span><span class="ff3">收<span class="_ _0"></span></span>集和<span class="_ _0"></span>数<span class="_ _0"></span>据分<span class="_ _0"></span><span class="ff3">析所<span class="_ _0"></span>获<span class="_ _0"></span>得<span class="_ _4"></span></span></span>的主<span class="_ _0"></span>要<span class="_ _0"></span>成<span class="ff3">果<span class="_ _0"></span></span>。<span class="_ _0"></span><span class="fc1">数<span class="_ _0"></span>据<span class="_ _0"></span>字<span class="ff3">典<span class="_ _0"></span></span>的<span class="_ _0"></span>基本<span class="_ _0"></span>内容<span class="_ _0"></span>有<span class="_ _0"></span>：数<span class="_ _0"></span>据项<span class="_ _0"></span>、<span class="_ _0"></span>数据<span class="_ _0"></span>结构<span class="_ _0"></span>、<span class="_ _0"></span>数</span></div><div class="t m0 x3 h3 y5e ff1 fs0 fc1 sc1 ls0 ws0">据<span class="ff3">流</span>、数据存储和<span class="ff3">处</span>理过程<span class="_ _1"> </span><span class="ff2">5<span class="_ _1"> </span></span>个部分。</div><div class="t m0 x6 h3 y5f ff1 fs0 fc0 sc0 ls0 ws0">第一章<span class="ff3">补</span>充作<span class="ff3">业</span>部分：</div><div class="t m0 x3 h3 y60 ff3 fs0 fc0 sc1 ls0 ws0">假<span class="ff1">设</span>教<span class="ff1">学管理规定：</span></div><div class="t m0 x4 h3 y61 ff2 fs0 fc0 sc1 ls0 ws0">①<span class="_ _1"> </span><span class="ff1">一个学生可选修多<span class="ff3">门课</span>，一<span class="ff3">门课</span>有<span class="ff3">若干</span>学生选修<span class="ff3">；</span></span></div><div class="t m0 x4 h3 y62 ff2 fs0 fc0 sc1 ls0 ws0">②<span class="_ _1"> </span><span class="ff1">一个<span class="ff3">教师</span>可讲<span class="ff3">授</span>多<span class="ff3">门课</span>，一<span class="ff3">门课只</span>有一个<span class="ff3">教师</span>讲<span class="ff3">授；</span></span></div><div class="t m0 x4 h3 y63 ff2 fs0 fc0 sc1 ls0 ws0">③<span class="_ _1"> </span><span class="ff1">一个学生选修一<span class="ff3">门课</span>，<span class="ff3">仅</span>有一个成<span class="ff3">绩</span>。</span></div><div class="t m0 x7 h3 y64 ff1 fs0 fc0 sc1 ls0 ws0">学生的<span class="ff3">属</span>性有学<span class="ff3">号</span>、学生<span class="ff3">姓名；教师</span>的<span class="ff3">属</span>性有<span class="ff3">教师</span>编<span class="ff3">号</span>，<span class="ff3">教师姓名；课</span>程的<span class="ff3">属</span>性有<span class="ff3">课</span>程<span class="ff3">号</span>、<span class="ff3">课</span>程<span class="ff3">名</span>。</div></div></div><div class="pi" data-data='{"ctm":[1.611850,0.000000,0.000000,1.611850,0.000000,0.000000]}'></div></div>
<div id="pf5" class="pf w0 h0" data-page-no="5"><div class="pc pc5 w0 h0"><img class="bi x0 y0 w1 h1" alt="" src="https://static.pudn.com/prod/directory_preview_static/6275e22f602a7856fe2a86a9/bg5.jpg"><div class="c x0 y1 w2 h2"><div class="t m0 x4 h3 y2 ff1 fs0 fc0 sc1 ls0 ws0">要<span class="ff3">求</span>：根据上述语义<span class="ff3">画出<span class="_ _1"> </span><span class="ff4">ER<span class="_ _1"> </span></span></span>图，要<span class="ff3">求</span>在图中<span class="ff3">画出</span>实体的<span class="ff3">属</span>性<span class="ff3">并注明</span>联系的类型<span class="ff3">；</span></div><div class="t m0 x4 h3 y3 ff3 fs0 fc0 sc1 ls0 ws0">解<span class="ff1">答：</span></div><div class="t m0 x8 h3 y65 ff1 fs0 fc0 sc0 ls0 ws0">第<span class="_ _1"> </span><span class="ff5 sc1">2<span class="_ _1"> </span></span>章关系数据库</div><div class="t m0 x3 h3 y66 ff1 fs0 fc0 sc1 ls0 ws0">一、选择题</div><div class="t m0 x3 h3 y67 ff2 fs0 fc0 sc1 ls0 ws0">1<span class="ff1">、关系数据库管理系统应能实现的<span class="ff3 fc1">专门<span class="ff1">关系</span>运<span class="ff1">算</span></span>包括 。</span></div><div class="t m0 x3 h3 y68 ff2 fs0 fc0 sc1 ls0 ws0"> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> A<span class="_ _2"></span><span class="ff1">．<span class="_ _0"></span><span class="ff3">排<span class="_ _0"></span></span>序<span class="_ _0"></span>、<span class="_ _0"></span><span class="ff3">索<span class="_ _0"></span>引<span class="_ _0"></span></span>、<span class="_ _0"></span>统<span class="_ _0"></span>计 <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _4"></span></span>B<span class="ff1">．<span class="_ _0"></span><span class="fc1">选<span class="_ _0"></span>择<span class="_ _0"></span>、<span class="_ _0"></span><span class="ff3">投<span class="_ _0"></span></span>影<span class="_ _0"></span>、<span class="_ _0"></span><span class="ff3">连<span class="_ _0"></span>接<span class="_ _0"></span></span> <span class="_ _0"></span></span> <span class="_ _0"></span> <span class="_ _2"></span></span>C<span class="_ _0"></span><span class="ff1">．<span class="_ _0"></span>关<span class="_ _0"></span>联<span class="_ _0"></span>、<span class="_ _0"></span>更<span class="_ _0"></span><span class="ff3">新<span class="_ _0"></span></span>、<span class="ff3">排<span class="_ _0"></span></span>序<span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _2"></span></span>D<span class="_ _0"></span><span class="ff1">．<span class="_ _0"></span><span class="ff3">显<span class="_ _0"></span>示<span class="_ _0"></span></span>、<span class="_ _0"></span><span class="ff3">打<span class="_ _0"></span>印<span class="_ _0"></span></span>、<span class="_ _0"></span>制<span class="_ _0"></span><span class="ff3">表</span></span></div><div class="t m0 x3 h3 y69 ff1 fs0 fc0 sc1 ls0 ws0">答案：<span class="ff2">B</span></div><div class="t m0 x3 h3 y6a ff2 fs0 fc0 sc1 ls0 ws0">2<span class="ff1">、关系模型中，一个<span class="fc1">关<span class="ff3">键</span>字</span>是 <span class="_ _0"></span> 。</span></div><div class="t m0 x9 h3 y6b ff2 fs0 fc0 sc1 ls0 ws0">A<span class="ff1">．可<span class="ff3">由</span>多个<span class="ff3">任意属</span>性<span class="ff3">组</span>成 </span>B<span class="ff1">．<span class="ff3">至</span>多<span class="ff3">由</span>一个<span class="ff3">属</span>性<span class="ff3">组</span>成 </span></div><div class="t m0 x9 h3 y6c ff2 fs0 fc0 sc1 ls0 ws0"> C<span class="ff1">．可<span class="ff3">由<span class="_ _0"></span></span><span class="fc1">一个或多<span class="_ _0"></span>个其<span class="ff3">值</span>能<span class="ff3">惟</span>一<span class="_ _0"></span><span class="ff3">标识该</span>关系模式中<span class="_ _0"></span><span class="ff3">任何元组</span>的<span class="ff3">属<span class="_ _0"></span></span>性<span class="ff3">组</span>成 <span class="_ _3"></span></span> </span>D<span class="ff1">．<span class="_ _0"></span>以上<span class="ff3">都</span>不是 <span class="_ _0"></span> <span class="_ _0"></span> 答</span></div><div class="t m0 x3 h3 y6d ff1 fs0 fc0 sc1 ls0 ws0">案：<span class="ff2">C</span></div><div class="t m0 x3 h3 y6e ff2 fs0 fc0 sc1 ls0 ws0">3<span class="_ _0"></span><span class="ff1">、<span class="ff3">自<span class="_ _0"></span>然<span class="_ _0"></span>连<span class="_ _0"></span>接<span class="_ _0"></span></span>是<span class="_ _0"></span>构<span class="_ _0"></span>成<span class="_ _0"></span><span class="ff3">新<span class="_ _0"></span></span>关<span class="_ _0"></span>系<span class="_ _0"></span>的<span class="_ _0"></span>有<span class="_ _0"></span><span class="ff3">效<span class="_ _0"></span>方<span class="_ _0"></span>法<span class="_ _0"></span></span>。一<span class="_ _0"></span><span class="ff3">般<span class="_ _0"></span>情<span class="_ _0"></span>况<span class="_ _0"></span></span>下<span class="_ _0"></span>，<span class="_ _0"></span><span class="ff3">当<span class="_ _0"></span></span>对<span class="_ _0"></span>关<span class="_ _0"></span>系<span class="_"> </span></span>R<span class="_ _d"> </span><span class="ff1">和<span class="_ _d"> </span></span>S<span class="_ _d"> </span><span class="ff1">使用<span class="_ _0"></span><span class="ff3">自<span class="_ _0"></span>然<span class="_ _0"></span>连<span class="_ _0"></span>接<span class="_ _0"></span>时<span class="_ _0"></span></span>，<span class="_ _0"></span>要<span class="_ _0"></span><span class="ff3">求<span class="_ _15"> </span></span></span>R<span class="_ _d"> </span><span class="ff1">和<span class="_ _d"> </span></span>S</div><div class="t m0 x3 h3 y6f ff3 fs0 fc0 sc1 ls0 ws0">含<span class="ff1">有一个或多个共有的 。</span></div><div class="t m0 x3 h3 y70 ff2 fs0 fc0 sc1 ls0 ws0"> A<span class="ff1">．<span class="ff3">元组</span> </span>B<span class="ff1">．行 </span>C<span class="ff1">．记录 </span>D<span class="_ _0"></span><span class="ff1 fc1">．<span class="ff3">属</span>性 <span class="fc0"> 答案：</span></span>D</div><div class="t m0 x3 h3 y71 ff2 fs0 fc0 sc1 ls0 ws0">4<span class="ff1">、关系<span class="ff3">运</span>算中<span class="ff3 fc1">花费时<span class="ff1">间可能最长</span></span>的<span class="ff3">运</span>算是 。</span></div><div class="t m0 x3 h3 y72 ff2 fs0 fc0 sc1 ls0 ws0"> A<span class="ff1">．<span class="ff3">投</span>影 </span>B<span class="ff1">．选择 </span>C<span class="ff1 fc1">．<span class="ff3">笛卡尔积</span><span class="fc0"> </span></span>D<span class="_ _0"></span><span class="ff1">．除 答案：</span>C</div><div class="t m0 x3 h3 y73 ff2 fs0 fc0 sc1 ls0 ws0">5<span class="ff1">．关系模式的<span class="ff3">任何属</span>性 。</span></div><div class="t m0 x3 h3 y74 ff2 fs0 fc0 sc1 ls0 ws0"> A<span class="_ _0"></span><span class="ff1 fc1">．不可<span class="_ _0"></span><span class="ff3">再</span>分 <span class="_ _0"></span><span class="fc0"> <span class="_ _0"></span> <span class="_ _0"></span> <span class="_ _4"></span></span></span>B<span class="ff1">．可<span class="ff3">再<span class="_ _0"></span></span>分 <span class="_ _0"></span></span>C<span class="ff1">．<span class="_ _0"></span><span class="ff3">命名</span>在<span class="ff3">该</span>关系<span class="_ _0"></span>模式中可以不<span class="_ _0"></span><span class="ff3">惟</span>一 <span class="_ _2"></span></span>D<span class="_ _0"></span><span class="ff1">．以上<span class="ff3">都</span>不是 <span class="_ _0"></span> 答</span></div><div class="t m0 x3 h3 y75 ff1 fs0 fc0 sc1 ls0 ws0">案：<span class="ff2">A</span></div><div class="t m0 x3 h3 y76 ff2 fs0 fc0 sc1 ls0 ws0">6<span class="ff1">．在<span class="fc1">关系<span class="ff3">代</span>数<span class="ff3">运</span></span>算中，<span class="ff3">五</span>种基本<span class="ff3">运</span>算为 。</span></div><div class="t m0 xa h5 y77 ff1 fs1 fc0 sc1 ls0 ws0">成</div><div class="t m0 xa h6 y78 ff3 fs1 fc0 sc1 ls0 ws0">绩</div><div class="t m0 xb h5 y79 ff3 fs1 fc0 sc1 ls0 ws0">教师<span class="ff1">编</span>号</div><div class="t m0 xc h6 y7a ff3 fs1 fc0 sc1 ls0 ws0">教师姓名</div><div class="t m0 xd h7 y7b ff1 fs2 fc0 sc1 ls0 ws0">学生</div><div class="t m0 xe h5 y7c ff1 fs1 fc0 sc1 ls0 ws0">选</div><div class="t m0 xe h5 y7d ff1 fs1 fc0 sc1 ls0 ws0">修</div><div class="t m0 xf h8 y7e ff2 fs1 fc0 sc1 ls0 ws0">m</div><div class="t m0 x10 h7 y7f ff3 fs2 fc0 sc1 ls0 ws0">课<span class="ff1">程</span></div><div class="t m0 x11 h9 y80 ff3 fs2 fc0 sc1 ls0 ws0">教师</div><div class="t m0 x12 h5 y81 ff1 fs1 fc0 sc1 ls0 ws0">讲</div><div class="t m0 x12 h6 y82 ff3 fs1 fc0 sc1 ls0 ws0">授</div><div class="t m0 x13 h8 y7e ff2 fs1 fc0 sc1 ls0 ws0">n</div><div class="t m0 x14 h8 y83 ff2 fs1 fc0 sc1 ls0 ws0">n</div><div class="t m0 x14 h8 y84 ff2 fs1 fc0 sc1 ls0 ws0">1</div><div class="t m0 x4 h5 y85 ff1 fs1 fc0 sc1 ls0 ws0">学</div><div class="t m0 x4 h6 y86 ff3 fs1 fc0 sc1 ls0 ws0">号</div><div class="t m0 x15 h6 y87 ff3 fs1 fc0 sc1 ls0 ws0">姓</div><div class="t m0 x15 h6 y88 ff3 fs1 fc0 sc1 ls0 ws0">名</div><div class="t m0 x16 h5 y89 ff3 fs1 fc0 sc1 ls0 ws0">课<span class="_ _16"> </span><span class="ff1">程</span></div><div class="t m0 x16 h6 y8a ff3 fs1 fc0 sc1 ls0 ws0">号</div><div class="t m0 x17 h5 y89 ff3 fs1 fc0 sc1 ls0 ws0">课<span class="_ _16"> </span><span class="ff1">程</span></div><div class="t m0 x17 h6 y8a ff3 fs1 fc0 sc1 ls0 ws0">名</div></div></div><div class="pi" data-data='{"ctm":[1.611850,0.000000,0.000000,1.611850,0.000000,0.000000]}'></div></div>
数据库综合
