There are several entities. The entities include employee status, employee certification. Other entities include education.The entities have different fields and the fields have different attributes. The fields have different attributes like text, number and time. Employee name has the attribute text; employee identification has the attribute number. In addition, employee certification date and education date and retirement date have the attribute date. Employee degree has the attribute text. There are three tables. That is certification table, education table and Employment status table. The tables have different fields as shown below. The link below contains the tables and the primary key and foreign key.
The three tables follow the principle of first normalization. The tables have primary key. The primary key in the tables is employee-id.The attributes in the three tables are atomic. Also, the tables do not have repeating fields. Like in the education table, the fields are name, employee identification, degree. The certification table has certification date, employee name and employee identification. Lastly, the employment status table has employee name, employee identification, retiring date and employment status. The fields in the table are unique. When the tables are linked, the tables will not follow the principle of normalization. This is because deleting common fields from the table like employee id will make all the tables’ loose data (Hoffer, Prescott & McFadden, 2007).
The table also follows the second normalization principles. The principles states that there should not be non trivial dependencies on the attributes. The attributes in the table depend on each other. For example, the table has fields like retirement date and the employment status affect each other. If the employment status of the employee changes the retirement date of the employee will change. So the attributes depend on each other. Thus, the table does not follow the principle of second Normalization. The table should be normalized by creating another table that includes retirement date and employment status (Hoffer, Prescott & McFadden, 2007).The third normalizations require the table not to have transitive dependencies.
In third normalization, a row must be identified by each column independently. The column should not depend on other columns to identify the row. For example, if the table has columns A, B, C, when one deletes column And B, it should not interfere with other columns.The tables follow the principle of third Normalization. This is because each column in the tables is independent. A row in the table is identified by a single column. For example, the columns employee name, employee identification, degree, retirement date, employment status are independent and each column holds unique information. The columns do not depend on each other to identify the row. Thus, the tables follow the third normalization principle (Hoffer, Prescott & McFadden, 2007).
Hoffer, J. A., Prescott, M. B, & McFadden, F.R. (2007).Modern Database Management. Edition8. Upper Saddle River, NJ. Pearson Prentice Hall