SQL数据库疑难，请教高手

1.select deptno,deptname,sex,sum(salary)/count(1) from emp,dept where dept.deptno=emp.deptno group by deptno,deptname,sex 2.update emp set salary=salary*1.2 where (getdate()-indate)365>=3 3.select * from emp where empno in(select empno,empname fr