Decomposing to Third Normal Form.

Added on - 24 Sep 2019

  • 2


  • 458


  • 101


  • 0


Showing pages 1 to 1 of 2 pages
Decomposing to Third Normal FormDelivery MethodYou will hand in output files contained in a tarball. The files will include the contents ofthe tables you have generated as a result of your decomposition to Third Normal Form(3NF).DescriptionThis project makes use of the database you installed for the first project. If you have notmodified the data or schemas associated with the original tables that were installed whenyou imported the database, you should be able to begin with the existing database.Otherwise, reinstall the employee database as described in Project 1.ProcedureYou will be given a table derived from the employee database and a set of functionaldependencies. You should complete the following steps1.Create the database table to be decomposed. Execute the following query:create view base as select dept_manager.emp_no,departments.dept_no,dept_name,dept_manager.from_date as dept_mgr_from_date,dept_manager.to_date as dept_mgr_to_date,title,titles.from_date as title_from_date,titles.to_date as title_to_datefrom departments, dept_manager, titleswhere departments.dept_no = dept_manager.dept_no anddept_manager.emp_no = titles.emp_no;This query yields a view calledbasethat you will need to decompose.2.What should be the key for this table?(emp_no, dept_no)3.You have as inputs the attributes of thebasetable, the key you just determined,and the following functional dependencies:a.If you know the department number, you know the department name.dept_no -> dept_nameb.There can only be one department manager at the same time.dept_no dept_mgr_from_date -> dept_mgr_to_datec.Each employee can only hold one title at the same time.emp_no title_from_date -> title_to_date title
You’re reading a preview

To View Complete Document

Become a Desklib Library Member.
Subscribe to our plans

Download This Document