计算机专业计算机技能测试

01'\r3、查询EE-201课成绩第3-5名的学生的学号。\r要求:运行成功,并生成正确的结果,打印SQL语句。\r3、\rselectsc.sno\rfrom(selecttl.grade\rfrom(selectdistincttop5grade\rfromsc\rwherecno=,ee-201'\rorderbygradedesc)astl(grade),\r(selectdistincttop2grade\rfromsc\rwherecno=,ee-201'\rorderbygradedesc)ast2(grade)\rwheretl.grade<t2.grade\r)ast3(grade)\rinnerjoinscont3.grade=sc.grade\rwherecno='ee-201'\r另一解更好:\rselectsc.sno\rfrom(selecttop3tl.grade\rfrom(selecttop5grade\rfromsc\rwherecno=,ee-201'\rorderbygradedesc)astl(grade)\rorderbytl.gradeasc\r)ast3(grade)\rinnerjoinscont3.grade=sc.grade\rwherecno=,ee-201'\r分步完成\r1、selecttop5gradeintotl\rfromsc\rwherecno=,ee-201,\rorderbygradedesc\r2、selecttop3tl.gradeintot2\rfromtl\rorderbytl.gradeasc\r3、selectsc.sno\rfromt2innerjoinscont2.grade=sc.grade\rwherecno=,ee-201,\r4、droptabletl\rdroptablet2