Payroll Management System Pasupuleti Ravi Teja U00298378

The PAYROLL SYSTEM is being designed to store the details of the pay being given to the employees. The company requires a database that needs to store the information of employees and their payroll system.

The information that this system should store about an employee is: Employee details like id, Name, birth place, birth date Type of name like first name, middle name, last name Type of address like address, city, state, country, postal code, home phone, cell Personal details like marriage status, educational details Details of department, compensation, earnings, deductions, cheque

The following symbols are used in designing the ER diagram:

ER Diagram:

Query to create Employee table with description of fields

Query to create Earning description

Functional Dependency Functional dependency (FD) is a set of constraints between two attributes in a relation. Functional dependency says that if two tuples have same values for attributes A1, A2,..., An, then those two tuples must have same values for attributes B1, B2, ..., Bn. Functional dependency is represented by an arrow sign (→) that is, X→Y, where X functionally determines Y. The left-hand side attributes determine the values of attributes on the right-hand side.  A functional dependency is a relationship between two attributes. Typically between the PK and other non-key attributes with in the table.

Normalization Normalization is a method to remove anomalies and bring the database to a consistent state. First Normal Form - As per First Normal Form, no two Rows of data must contain repeating group of information. Second Normal Form - No non-prime attribute is dependent on the proper subset of any candidate key of the table. Third Normal Form - Transitive functional dependency of non-prime attribute on any super key should be removed

Normalization In other words 3NF can be explained like this: A table is in 3NF if it is in 2NF and for each functional dependency X-> Y at least one of the following conditions hold: X is a super key of table and Y is a prime attribute of table Boyce-Codd Normal Form - It is an advance version of 3NF that’s why it is also referred as 3.5NF. BCNF is stricter than 3NF. A table complies with BCNF if it is in 3NF and for every functional dependency X->Y, X should be the super key of the table.

ER DIAGRAM | BCNF NORMALIZATION

What I learnt from the project: For this project I had to create an ER diagram, create tables based on the diagram, insertion of tuples, creating sql queries I got to know the real meaning, what a strong entity is and what is a weak entity, what is a primary key, partially unique key, meaning of the symbols that are used in an ER diagram, how to represent relationships, how to represent different entities, I got to know on how to represent an attribute, types of attribute like multivalued, derived etc. types of relationships used. While creating the tables, I leant a lot of sql statements used to create, modify, update and delete the tables, statements to see all possible statements, description of tables, code to limit the size of answer, code to see the values in tables, code to insert tuples.