i have 3 tables
student(studentid, teacherid)teacher(teacherid, number)- a temp table
studentupdate(studentid, teachernumber)
how update student.teacherid values studentupdate.teachernumber?
please see difference between teacherid , teacher number. 1 pk , 1 nvarchar column. in advance.
you can using below query. assuming have 1 teacher each student
update st set st.teacherid = t.teacherid student st inner join studentupdate su on su.studentid = st.studentid inner join teacher t on t.number = su.teachernumber 