Suggest one of the problems that normalization seeks to solve within a database. Describe one example of your suggested problem and explain the overall benefit that normalization would provide. (Note: Your example can be hypothetical or use the university business function or operation).
Identify the key determinants that could affect the degree of normalization of a database. Justify your response. Next, identify the aspects of the database design that can be denormalized. Explain the key ways in which the business rules support the degree of normalization and the elements that can be denormalized.
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Example
Consider a university database that stores information about students, courses, and enrollments. If the database is not normalized, the student's name and address may be stored in multiple tables, such as the students table, the courses table, and the enrollments table. This would be redundant, as the student's name and address only need to be stored once.
Benefits of normalization
Normalizing a database can help to reduce data redundancy and improve the overall design of the database. This can lead to a number of benefits, including:
- Reduced storage space requirements
- Improved data consistency
- Reduced difficulty in maintaining the database
- Improved performance
- Increased flexibility
Key determinants that could affect the degree of normalization of a database
There are a number of factors that can affect the degree of normalization of a database, including:
- The complexity of the data: The more complex the data, the more likely it is that data redundancy will occur.
- The performance requirements of the database: If the database needs to be able to process queries quickly, then it may be necessary to denormalize some of the tables.
- The need for data integrity: If it is important to maintain data integrity, then the database should be normalized to a higher degree.
Aspects of the database design that can be denormalized
Some of the aspects of the database design that can be denormalized include:
- Table relationships: Denormalizing table relationships can improve the performance of certain queries.
- Data attributes: Denormalizing data attributes can also improve the performance of certain queries.
How business rules support the degree of normalization
Business rules can help to determine the degree of normalization of a database. For example, if a business rule states that a student's name and address must be unique, then the students table should be normalized to a higher degree.
Elements that can be denormalized
Some of the elements that can be denormalized include:
- Frequently accessed data: Denormalizing frequently accessed data can improve the performance of certain queries.
- Reference data: Denormalizing reference data can also improve the performance of certain queries.
Conclusion
Normalizing a database can help to reduce data redundancy and improve the overall design of the database. However, it is important to balance the benefits of normalization with the performance requirements of the database and the need for data integrity. Business rules can help to determine the appropriate degree of normalization for a database.
Sample Answer
Problem that normalization seeks to solve
One of the problems that normalization seeks to solve is data redundancy. Data redundancy occurs when the same data is stored in multiple places in a database. This can lead to a number of problems, including:
- Increased storage space requirements: Redundant data takes up more storage space, which can be costly for organizations.
- Data inconsistency: When redundant data is updated, it is important to update all occurrences of the data to ensure consistency. If this is not done, the data may become inconsistent, which can lead to errors and problems.
- Difficulty in maintaining the database: A database with redundant data can be more difficult and time-consuming to maintain.