Relational Data Model Assignment Example | Topics and Well Written Essays - 1000 words

Relational Data Model - Assignment Example The attribute "is leader" should be removed from the table Candidate because this information already exists in the table Party. It is possible to get to know if a Candidate is leader of any party with looking through references to leaders in the table Party. .. First_name Middle_name Last_name address gender date of birth Party Pk_id Fk_leader name address date established Candidate Pk_id Fk_electorate Fk_party First_name Middle_name Last_name address gender date of birth is leader Second normal form (2NF) further addresses the concept of removing duplicative data: Meet all the requirements of the first normal form. Remove subsets of data that apply to multiple rows of a table and place them in separate tables. Create relationships between these new tables and their predecessors through the use of foreign keys. (Chapple 2005) So, personal information, such as name (first, middle, last), address, gender, and date of birth can be taken apart into separate table Person. It also should have a primary key named Pk_id. Then tables Elector and Candidate should reference to it via secondary (foreign) key Fk_person. Therefore there are 5 tables in the relational database schema for the 2NF: Person Pk_id First_name Middle_name Last_name address gender date of birth Electorate Pk_id unique name number of registered voters Elector Pk_id Fk_electorate Fk_party_vote Fk_candidate_vote Fk_person Party Pk_id Fk_leader name address date established Candidate Pk_id Fk_electorate Fk_party Fk_person is leader Third normal form (3NF) goes one large step further: Meet all the requirements of the second normal form. Remove columns that are not dependent upon the primary key. (Chapple 2005) The attribute "is leader" should be removed from the table Candidate because this information already exists in the table Party. It is possible to get to know if a Candidate is leader of any party with looking through references to leaders in the table Party. There's no attributes that are not dependent upon the primary key. Here are