解析:<p>【答案】连接</p><p>【解析】连接(Join)是从两个或多个关系的笛卡儿乘积中选取满足一定条件的记录。</p><p>例如,假设现在还有一个学生成绩表 courseInfo Tab,其结构及内容如下表所示:</p><p style="text-indent:253px"><strong><span style="font-family: 宋体;font-size: 14px"><span style="font-family:宋体">学生成绩表</span></span></strong></p><table width="598"><tbody><tr style="height:17px" class="firstRow"><td width="199" valign="top" style="padding: 0px 7px; border-width: 1px; border-color: windowtext; background: rgb(164, 164, 164);"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">学号(StuID)</span></p></td><td width="199" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top-width: 1px; border-top-color: windowtext; border-bottom-width: 1px; border-bottom-color: windowtext; background: rgb(164, 164, 164);"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">课程号(CourseID)</span></p></td><td width="199" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top-width: 1px; border-top-color: windowtext; border-bottom-width: 1px; border-bottom-color: windowtext; background: rgb(164, 164, 164);"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">课程成绩(Score)</span></p></td></tr><tr><td width="199" valign="top" style="padding: 0px 7px; border-left-width: 1px; border-left-color: windowtext; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">200601001</span></p></td><td width="199" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">2033</span></p></td><td width="199" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">69</span></p></td></tr><tr><td width="199" valign="top" style="padding: 0px 7px; border-left-width: 1px; border-left-color: windowtext; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">200601002</span></p></td><td width="199" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">2034</span></p></td><td width="199" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">89</span></p></td></tr><tr><td width="199" valign="top" style="padding: 0px 7px; border-left-width: 1px; border-left-color: windowtext; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">200601003</span></p></td><td width="199" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">2033</span></p></td><td width="199" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">90</span></p></td></tr><tr><td width="199" valign="top" style="padding: 0px 7px; border-left-width: 1px; border-left-color: windowtext; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">200601001</span></p></td><td width="199" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">2011</span></p></td><td width="199" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">86</span></p></td></tr><tr><td width="199" valign="top" style="padding: 0px 7px; border-left-width: 1px; border-left-color: windowtext; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">200601005</span></p></td><td width="199" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">1034</span></p></td><td width="199" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">94</span></p></td></tr><tr><td width="199" valign="top" style="padding: 0px 7px; border-left-width: 1px; border-left-color: windowtext; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">200601001</span></p></td><td width="199" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">2035</span></p></td><td width="199" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">85</span></p></td></tr><tr><td width="199" valign="top" style="padding: 0px 7px; border-left-width: 1px; border-left-color: windowtext; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">200601007</span></p></td><td width="199" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">2037</span></p></td><td width="199" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style=";font-family:宋体;font-size:14px">91</span></p></td></tr></tbody></table><p>现要求查找到学生张常的所有成绩信息,并要求列出其学号、姓名、课程号和课程成绩,结果如下表所示:</p><p style="text-indent:183px"><strong><span style="font-family: 宋体;font-size: 14px"><span style="font-family:宋体">查询学生张常的所有课程成绩</span></span></strong></p><table width="598"><tbody><tr class="firstRow"><td width="149" valign="top" style="padding: 0px 7px; border-width: 1px; border-color: windowtext; background: rgb(164, 164, 164);"><p style="text-align:center"><span style="font-family: 宋体;font-size: 14px">学号(StuID)</span></p></td><td width="149" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top-width: 1px; border-top-color: windowtext; border-bottom-width: 1px; border-bottom-color: windowtext; background: rgb(164, 164, 164);"><p style="text-align:center"><span style="font-family: 宋体;font-size: 14px">姓名(Name)</span></p></td><td width="149" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top-width: 1px; border-top-color: windowtext; border-bottom-width: 1px; border-bottom-color: windowtext; background: rgb(164, 164, 164);"><p style="text-align:center"><span style="font-family: 宋体;font-size: 14px">课程号(CourseID)</span></p></td><td width="149" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top-width: 1px; border-top-color: windowtext; border-bottom-width: 1px; border-bottom-color: windowtext; background: rgb(164, 164, 164);"><p style="text-align:center"><span style="font-family: 宋体;font-size: 14px">课程成绩(Score)</span></p></td></tr><tr><td width="149" valign="top" style="padding: 0px 7px; border-left-width: 1px; border-left-color: windowtext; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style="font-family: 宋体;font-size: 14px">200601001</span></p></td><td width="149" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style="font-family: 宋体;font-size: 14px">张常</span></p></td><td width="149" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style="font-family: 宋体;font-size: 14px">2033</span></p></td><td width="149" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style="font-family: 宋体;font-size: 14px">69</span></p></td></tr><tr><td width="149" valign="top" style="padding: 0px 7px; border-left-width: 1px; border-left-color: windowtext; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style="font-family: 宋体;font-size: 14px">200601001</span></p></td><td width="149" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style="font-family: 宋体;font-size: 14px">张常</span></p></td><td width="149" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style="font-family: 宋体;font-size: 14px">2011</span></p></td><td width="149" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style="font-family: 宋体;font-size: 14px">86</span></p></td></tr><tr><td width="149" valign="top" style="padding: 0px 7px; border-left-width: 1px; border-left-color: windowtext; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style="font-family: 宋体;font-size: 14px">200601001</span></p></td><td width="149" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style="font-family: 宋体;font-size: 14px">张常</span></p></td><td width="149" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style="font-family: 宋体;font-size: 14px">2035</span></p></td><td width="149" valign="top" style="padding: 0px 7px; border-left: none; border-right-width: 1px; border-right-color: windowtext; border-top: none; border-bottom-width: 1px; border-bottom-color: windowtext;"><p style="text-align:center"><span style="font-family: 宋体;font-size: 14px">85</span></p></td></tr></tbody></table><p><br/></p>