Experiment 4 3-group by data query, etc.

Experiment 4 database queries

First, the Experiment:

1, Group by statement

2, Having Statement

3, Order by the statement

4, Limit statement

5, Union statement

6, Handler statement

Second, the pilot project: staff management database

Staff management for enterprise database management, database named YGGL in, YGGL database consists of three tables: Employees (employee information table), Departments (department information table), Salary (staff salaries Fact Sheet).

Third, the experimental procedures required to complete the following :( command)

1, by department employees working in the sector;

2, respectively, statistics males and female employees;

3, find the name of the department and the number of employees number of employees more than two people;

4, grouped according to statistics the number of academic staff of various qualifications;

5, according to staff qualifications, gender statistics, the number of all kinds of education;

Number 6, according to staff qualifications, various degrees of gender statistics and produces a result set, including the number of male workers for each degree, the number of female workers, the total number;

7, by gender, statistics department number the number of departments, including the number of employees in each department male and female number of employees and the total number;

8, look for the number of workers than male department No. 2, the number of male workers;

9, the employee information sorted in descending order by date of birth;

10, the number of employees paid by revenue from small to large;

11, according to years of service packets, people counting each working years, and in accordance with the number of small to large;

12. Find five records from the beginning of Article 3 records employee information table;

13, find the number of employees is greater than the income of male workers in 2000, the name, income, claim 5 rows before the show;

14, employee name query information from the employee table, gender, query department number, department name from the department information table and two union query results into a single result set;

15, the query from the employee information table employee number, name, query department number, department name from the department information table and two union query results into a single result set, the result will be sorted according to staff number, to display the result set the first 15 records;