Oracle之row_number函数

create table employee (empid int ,deptid int ,salary decimal(10,2))
insert into employee values(1,10,5500.00);
insert into employee values(2,10,4500.00);
insert into employee values(3,20,1900.00);
insert into employee values(4,20,4800.00);
insert into employee values(5,40,6500.00);
insert into employee values(6,40,14500.00);
insert into employee values(7,40,44500.00);
insert into employee values(8,50,6500.00);

insert into employee values(9,50,7500.00);

给工资评定等级：

SELECT employee.*, Row_Number() OVER (partition by deptid ORDER BY salary desc) rank FROM employee