SQL Server 2019

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CREATE TABLE employees_list   
(employeeID int identity(1,1),   
employeeName varchar(25))  
   
  
INSERT INTO employees_list VALUES ('Kevin'),('Charles')  
 
   
CREATE TABLE hourlyRates   
(employeeID int,   
rate int,   
rateDate date)   
  
INSERT INTO hourlyRates VALUES (1, 28, '2016-01-01'),   
                               (1, 39, '2016-02-01'),  
                               (2, 43, '2016-01-01'),  
                               (2, 57, '2016-02-01')  
  
  
CREATE TABLE workingHours   
(employeeID int,   
startdate datetime,   
enddate datetime)

INSERT INTO workingHours VALUES (1, '2016-01-01 09:00', '2016-01-01 17:00'),  
                                (1, '2016-01-02 09:00', '2016-01-02 17:00'),  
                                (1, '2016-02-01 10:00', '2016-02-01 16:00'),  
                                (1, '2016-02-02 11:00', '2016-02-02 13:00'),  
                                (2, '2016-01-01 10:00', '2016-01-01 16:00'),  
                                (2, '2016-01-02 08:00', '2016-01-02 14:00'),  
                                (2, '2016-02-01 14:00', '2016-02-01 19:00'),  
                                (2, '2016-02-02 13:00', '2016-02-02 16:00')

14 rows affected

employeeName	Month	Total Salary
Charles	January	516
Kevin	January	448
Charles	February	456
Kevin	February	312