Entities: Employees (Employee code, Full name, Age, Sex, Address, Phone number, Passport data, Positio

Entities:

1. Employees (Employee code, Full name, Age, Sex, Address, Phone number, Passport data, Position code).
2. Positions (Position Code, Position Name, Salary, Responsibilities, Requirements).
3. Rooms (Room Code, Name, Capacity, Description, Cost, Employee Code).
4. Services (Service Code, Name, Description, Cost).
5. Clients (full name, passport data, check-in date, check-out date, room code, service code 1, service code 2, service code 3, cost, employee code).

Queries:

1. Human Resources Department (joins the "Employees" and "Positions" tables by the "Position Code" field).
2. Numbers (joins the "Employees" and " Rooms" tables by the "Employee Code" field).
3. Clients (Joins the tables "Clients", "Rooms", "Services" and "Employees" in the fields "Rooms code", "Service code", "Service code 1", "Service code 2", "Service code 3" and "Employee Code").

Parameter queries:

1. Display employees of specified positions (based on the request "Human Resources").
2. Display clients living in specified rooms (based on the "Clients" query).
3. Display rooms of specified capacities (based on the request "Numbers").