sql - How to count the number of students taught by each teacher? -


i have database has following tables

courses: courseid*, coursename, teacherid teachers: teacherid*, teachername students: studentid*, studentname studentcourses: courseid*, studentid*

legend: * primary key.

how can write query produces produces number of students taught each teacher?

for example

teachername, count bob 15 sarah 5 zubair 1

edit 

select "teachername", count(*) courses inner join teachers on courses."teacherid" = teachers."teacheri" join sutdentcourses on sutdentcourses."courseid" = courses."courseid" group "teachername" order "teachername";

you need make join between tables teachers, courses , studentcourses, group records teachername , count studentid.

select teachername, count(studentid) teachers join courses using(teacherid) join studentcourses using(courseid) group teachername

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