f（13）检索学生姓名及其所选修课程的课程号和成绩selects
osumscorefromscwherescore60a
ds
oi
selects
ofromscgroupbys
ohavi
gcou
ts
o4groupbys
oorderbysumscoredesc（14）查询c001课程比c002课程成绩高的所有学生的学号selectfromSCawhereac
oc001a
dexistsselectfromscbwherebc
oc002a
dascorebscorea
das
obs
o（15）查询平均成绩大于60分的同学的学号和平均成绩selects
oavgscorefromscgroupbys
ohavi
gavgscore60（16）查询姓刘的老师的个数selectcou
tfromteacherwheret
like刘（17）查询没学过谌燕老师课的同学的学号、姓名selectfromsstwherests
o
oti
selectdisti
cts
ofromscsjoi
courseco
sc
occ
ojoi
teacherto
ct
ott
owheret
ame谌燕（18）查询学过c001并且也学过编号c002课程的同学的学号、姓名selectstfromscajoi
scbo
as
obs
ojoi
ssto
sts
oas
owhereac
oc001a
dbc
oc002a
dsts
oas
o（19）查询学过谌燕老师所教的所有课的同学的学号、姓名selectstfromsstjoi
scso
sts
oss
ojoi
courseco
sc
occ
ojoi
teacherto
ct
ott
owherett
ame谌燕
（19）查询课程编号c002的成绩比课程编号c001课程低的所有同学的
f学号、姓名selectfromsstjoi
scao
sts
oas
ojoi
scbo
sts
obs
owhereac
oc002a
dbc
oc001a
dascorebscore（20）查询所有课程成绩小于60分的同学的学号、姓名selectstsscorefromsstjoi
scso
sts
oss
ojoi
courseco
sc
occ
owheresscore60
（21）查询没有学全所有课的同学的学号、姓名selectfromswheres
oi
selects
ofromselectsts
occ
ofromsstcrossjoi
coursecmi
usselects
oc
ofromsc（22）查询每门课程被选修的学生数selectc
ocou
ts
ofromscgroupbyc
o
（23）查询出只选修了一门课程的全部学生的学号和姓名selectscs
osts
cou
tc
ofromsstleftjoi
sco
scs
osts
ogroupbysts
scs
ohavi
gcou
tc
o1（24）查询男生、女生人数selectsexcou
tfromsgroupbysex
（25）查询姓张的学生名单selectfromswheres
like张（26）查询平均成绩大于85的所有学生的学号、姓名和平均成绩
fselectsts
osts
avgscorefromsstleftjoi
sco
scs
osts
ogroupbysts
osts
havi
gavgscore85（27）查询课程名称为数据库，且分数低于60的学生姓名和分数selects
scorefromsstsccoursecwherests
oscs
oa
dscc
occ
oa
dcc
数据库a
dscscore60（28）查询所有学生的选课情况selectsts
osts
cc
fromsstsccoursecwherescs
osts
oa
dscc
occ
o（29）查询任何一门课程成绩在70分以上的姓名、课r