1.How are many-to-many relationships addressed in the relational model Essay

1.How are many-to-many relationships addressed in the relational model Provide a specific example other than the one in your textbook. Illustrate your answer using IE Crows Foot E-R diagrams - Essay Example In a relational model, the many-to-many relationship cannot directly be modeled. Such a relationship has to be converted into multiple one-to-many relationships first. Therefore, a many-to-many relationship is represented in the form of three tables in the model; the two original tables and a junction table. For the country-language example stated above, the relationship is formed as shown in the figure below. The many-to-many relationship between country and language is converted into two one-to-many relationships between the two entities and the the junction table. In the junction table (CountryLanguage), the unique primary key is a composite key (CountryID, LanguageID) which is formed by the two foreign keys which refer to the primary keys of the ‘country’ (CountryID) and ‘language’ (LanguageID)