SELECT*

from employees

no, you are refering to a fact table used to record activity over time. employee records should be in a dimension table, the fact table should have a foreign key to the employees table. The R in rdbms stands for relational. You want to understand the rules of normalization for oltp and denormalized star schema for olap.

Yes. This is referred to as a self reference or circular relationshiop with just one Table. One classic example is an Employee table and some employees are managers and hence have child Employees.

a good personnel has a sufficient knowledge of food preparation and service know the uses and function of food service tools and equipment has a good working relations with his\her employees and possesses management skills and has a knowledge on table etiquette and details in waiting on the table.