练习题 1. 列出所有员工的姓名、部门名称和工资 Select e.ename,d.dname,e.sal From emp e,dept d Where e.deptno=d.deptno; 2. 列出所有部门的详细信息和部门人数 Select d.deptno,d.dname, d.loc,count(e.empno) From emp e,dept d Where e. deptno(+)=d.deptno Group by d.deptno,d.dname,d.loc; 3. 列出所有员工的年工资、所在部门名称，按年薪升序排序 Select e.ename,e.sal*12 income,d.dname From emp e,dept d Where e.deptno=d.deptno Order by income;