多表查询sql语句count.doc

多表查询sq?l语句cou?nt? ?篇一： SQ?L语句多表查询SQL?语句多表查询： 问题及描述： -?- ?1.?学生表 St?ud?en?t(?S#?,S?na?me?,S?ag?e,?Ss?ex?) ?--?S#? 学生编号,Sn?am?e ?学生姓名,S?ag?e ?出生年月,S?se?x ?学生性别 -?-2?.课程表 C?ou?rs?e(?C#?,C?na?me?,T?#)? -?-C?# ?--?课程编号,C?na?me? 课程名称,T#? 教师编号 --?3.?教师表 Te?ac?he?r(?T#?,T?na?me?) ?--?T#? 教师编号,Tn?am?e ?教师姓名 -?-4?.成绩表 S?C(?S#?,C?#,?sc?or?e)? -?-S?# ?学生编号,C?# ?课程编号,s?co?re? 分数 */? -?-创建测试数据 cr?ea?te? t?ab?le? S?tu?de?nt?(S?# ?va?rc?ha?r ?(1?0)?,S?na?me? n?va?rc?ha?r ?(1?0)?,S?ag?e ?da?te?ti?me?,S?se?x ?nv?ar?ch?ar? (?10?))? i?ns?er?t ?in?to? S?tu?de?nt? v?al?ue?s(? 0?1 ?, ?N ?赵雷 ,? 1?99?0-?01?-0?1 ?, ?N ?男 ) ?in?se?rt? i?nt?o ?St?ud?en?t ?va?lu?es?( ?02? ,? N? 钱电 , ?19?90?-1?2-?21? ,? N? 男 )? i?ns?er?t ?in?to? S?tu?de?nt? v?al?ue?s(? 0?3 ?, ?N ?孙风 ,? 1?99?0-?05?-2?0 ?, ?N ?男 ) ?in?se?rt? i?nt?o ?St?ud?en?t ?va?lu?es?( ?04? ,? N? 李云 , ?19?90?-0?8-?06? ,? N? 男 )? i?ns?er?t ?in?to? S?tu?de?nt? v?al?ue?s(? 0?5 ?, ?N ?周梅 ,? 1?99?1-?12?-0?1 ?, ?N ?女 ) ?in?se?rt? i?nt?o ?St?ud?en?t ?va?lu?es?( ?06? ,? N? 吴兰 , ?19?92?-0?3-?01? ,? N? 女 )? i?ns?er?t ?in?to? S?tu?de?nt? v?al?ue?s(? 0?7 ?, ?N ?郑竹 ,? 1?98?9-?07?-0?1 ?, ?N ?女 ) ?in?se?rt? i?nt?o ?St?ud?en?t ?va?lu?es?( ?08? ,? N? 王菊 , ?19?90?-0?1-?20? ,? N? 女 )? c?re?at?e ?ta?bl?e ?Co?ur?se?(C?# ?va?rc?ha?r ?(1?0)?,C?na?me? n?va?rc?ha?r ?(1?0)?,T?# ?va?rc?ha?r ?(1?0)?) ?in?se?rt? i?nt?o ?Co?ur?se? v?al?ue?s(? 0?1 ?, ?N ?语文 ,? 0?2 ?) ?in?se?rt? i?nt?o ?Co?ur?se? v?al?ue?s(? 0?2 ?, ?N ?数学 ,? 0?1 ?) ?in?se?rt? i?nt?o ?Co?ur?se? v?al?ue?s(? 0?3 ?, ?N ?英语 ,? 0?3 ?) ?cr?ea?te? t?ab?le? T?ea?ch?er?(T?# ?va?rc?ha?r ?(1?0)?,T?na?me? n?va?rc?ha?r ?(1?0)?) ?in?se?rt? i?nt?o ?Te?ac?he?r ?va?lu?es?( ?01? ,? N? 张三 ) ?in?se?rt? i?nt?o ?Te?ac?he?r ?va?lu?es?( ?02? ,? N? 李四 ) ?in?se?rt? i?nt?o ?Te?ac?he?r ?va?lu?es?( ?03? ,? N? 王五 ) ?cr?ea?te? t?ab?le? S?C(?S#? v?ar?ch?ar? (?10?),?C#? v?ar?ch?ar? (?10?),?sc?or?e ?de?ci?ma?l(?18?,1?))? i?ns?er?t ?in?to? S?C ?va?lu?es?( ?01? ,? 0?1 ?, ?80?) ?in?se?rt? i?nt?o ?SC? v?al?ue?s(? 0?1 ?, ?02? ,? 9?0)? i?ns?er?t ?in