问答 教师表 A (tno，tname)，课程表 B (tno，cno，cname)，请教大神，列出每个教师的课程数，这个 SQL 怎么写啊
1）列出王姓教师所教的所有课程，按课程名排序；
2）列出每个教师的课程数；
select B.* from B join A on B.tno = A.tno where A.tname like '王%';
select A.tname, count(0) from B join A on B.tno = A.tno group by A.tno;
这样子？
select B.* from B join A on B.tno = A.tno where A.tname like '王%';
select A.tname, count(0) from B join A on B.tno = A.tno group by A.tno;
这样子？
(1) select a.tno,b.tname,a.cname from B a inner join (select tno,tname from A where tname like '王%') b no=b.tno order by a.cname ASC;
（2）select b.tname,a.tno,a.count from (select tno,count(*) count from B group by tno) a right join A b on a.tno=b.tno;
select B.cname from B ,A where A.tno=B.ton and A.tname like "王%"order by B.cname
select A.tname , D.c from (select tno,count(*) AS c from B group by tno) D ,A where D.tno =A.tno