OnCall Scheduler

I am looking for ideas on how to automate the scheduling of On Call Employees. Thinking to do this a month at a time but then their is the 4/5 week thing. On Call Rotation is the Goal by 1st to last.?

This is my schema.



tblSchedules

SchedID PK

EmpID FK Linked to tblEmployees

StartDate Starting Date of Being OnCall

EndDate Ending Date of Being OnCal

OnCall Current OnCall Month





tblEmployees

EmployeeID PK

OnCallElligible Yes/No True/False

OnCall Scheduler