操作sql表获取一天超额预定的员工

Question

I have 3 Tables

1. Employees (empid, lname, fname, emptype, cellphone, homphone, ftpt)
2. Schedule(date, empid, dept_name, start_time, shift_length)
3. Departments(dept_name, dept manager)`

We have to generate a table listing all employees who are overbooked by being scheduled more than once a day.

The final table after the select statement should look like this :

it is ordered by the employee ID.

Here is the create table for the 3 tables:

CREATE TABLE Departments(department_name VARCHAR(30));
CREATE TABLE Employees(empid int PRIMARY KEY NOT NULL, lname VARCHAR(20) NOT NULL, fname VARCHAR(20) NOT NULL, emptype VARCHAR(5) NOT NULL, cellphone VARCHAR(20), homephone VARCHAR(20), ftpt VARCHAR(3) NOT NULL);
CREATE TABLE Schedule(date VARCHAR(20) NOT NULL, empid INT NOT NULL, department VARCHAR(30) NOT NULL, start_time VARCHAR(5) NOT NULL, shift_length INT NOT NULL );

Sample data Schedule EMPLOYEES

Files with data - https://drive.google.com/drive/folders/1hSf4rbGOvqrTZVyPaveF6fUAKB29Q2o_?usp=sharing

Answer 1

Some of the column names you gave are inconsistent, so you may need to change some of them to match what is actually in your database. But this should get you started.

SELECT empid, lname as lastName, fname as firstName, date as [OVERBOOKED DATE], start_time as sfrom, Departments.dept_name as dname, dept_manager as MANAGER FROM Employees JOIN Schedule ON Employees.empid=Schedule.empid JOIN Departments on Schedule.dept_name=Departments.dept_name WHERE empid IN (SELECT empid FROM Schedule WHERE COUNT(*) > 1 GROUP BY date, empid)