Relational Database Assignment Example | Topics and Well Written Essays - 750 words

Relational Database - Assignment Example This assists the user in matching the data with the help of common characteristics contained in the data set including the relation or tables. Relationships play a role in making the data more organized and manageable. This helps the user in perceiving the real concept of design of the database. This also increases the integrity of data through proper arrangement of the data which is logically related into distinct relations. Thinking about the efficiency of database and relationships is an essential component of the normalization process (yaldex.com, n.d.). A relationship is a prime component of the relational database as it develops an association between the logically related pair of tables. The data contained by each of the two tables is the bonding agent between the pair of tables. Relationship if properly defined promotes relationship-level integrity, that in turn ensures the reliability and strength of the relationship (eTutorials, 2012). In addition to that, relationships mak e it possible for the user to perform algebraic operations upon the tables. Division of the elements of a data into the related tables is one of the most challenging tasks of designing a relational database. Once the user is all set to begin work with the data, the user depends upon the relationships among individual tables so that the data can be pulled together in purposeful ways. For example, information about a particular order is of no use if the user does not know the customer who has placed it. Nevertheless, the customer and the information about his/her order are not stored in the same table. Instead of this, the user stores the customer data and the order in two tables that are interrelated. The very relationship between the tables is used to view both the order and the customer data simultaneously. Relationships are the cornerstone when the normalized tables play the role of foundations of the relational database Relationships also help prevent the redundant data in a rela tional database (Microsoft Support, 2011). Defining Relationships between Two Tables A very essential characteristic of the database design is the use of relationships between tables. Defining relationships between tables is very essential for efficient working of the system. â€Å"Relationships between tables are often missing for performance reasons† (Olson, 2009, p. 111). Relationships between two tables are defined through the database system which depends upon matching the values contained in the two tables. When matching values are located, the database system retrieves data from the two tables so that a virtual record can be established. For example, let’s suppose an individual wants to view all the perfumes made by a certain brand. In this example, the database system would locate matching values between the tables of Perfumes and Brands. It is noteworthy here that in a vast majority of cases, the record which results is dynamic that essentially means that chan ges which are made to the virtual record normally identify the path to the underlying table. The matching values that the database system finds include the foreign and primary key values. It is not necessary for a relational model to base the relationship upon a primary key. The user can make use of any candidate key from the table. However, the standard practice requires the use of primary key only. When the primary key of one table is put into another table, a foreign key is formed. All a user needs to do is add the field of the primary key as a foreign key to the