Databases

1.) Describe the use of nulls databases

Assignment: Problem # 3 from Chapter # 6. Normalize a set of data to 3rd normal form by creating relational schemas, dependency diagrams and an Entity Relationship Diagram (crow’s foot notation). For this lab, complete problem # 3 in Chapter 6. Be sure to complete each letter (a thru d) for the problem. The ERD for letter d must be completed with the use of Microsoft Visio. Attach all files to a submission to the drop box for Lab # 03. Notes: (1) Relational schema is defined in section 4.1.2 in chapter 4 of the textbook. (2) Dependency diagram is defined in section 6.3.1 in chapter 6 of the textbook. (3) An example of a crow’s foot ERD can be found in chapter 4, figure 4.35. (4) Microsoft Visio is available to you in VLABS or you may decide to obtain the software for your own personal use. Microsoft Visio software is available free of charge through Penn State’s membership in DREAMSPARK (formerly MSDNAA). If you are interested in obtaining your own free copy of Visio, please refer to the file Dreamspark under Lesson 01: Introduction Getting Started. Problem 3:3.3.    Using the INVOICE table structure shown in Table P6.3 do the following:a.     Write the relational schema, draw its dependency diagram, and identify all dependencies, including all partial and transitive dependencies. You can assume the table does not contain repeating groups and that an invoice number references more than 1 product. (Hint: This table uses a composite primary keys.)b.     Remove all partial dependencies, write the relational schema, and draw the new dependency diagrams. Identify the normal forms for each table structure you created.c.     Remove all transitive dependencies, write the relational schema, and draw the new dependency diagrams. Also identify the normal forms for each table structure you created.d.     Draw the Crow’s Foot ERD.