Evaluate the data integrity, security, and availability issues related to relational databases.
Instructions
Include the below numbering scheme in the submission. DO NOT include the Questions or other content from the instructions.
Part 1)
Identify 4 database constraints (examples can include: Not NULL, primary key, unique, domain; there can be different ones as well) and data integrity, security, and availability issues related to relational databases.
Part 2)
HINT: Review the Normalization Process: Parts and Suppliers One-to-Many Example in the Terms and Concepts discussion.
Full Answer Section
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Foreign Key Constraint:
- Data Integrity Issue: Orphaned records can occur if a foreign key references a non-existent primary key in the related table. This can lead to inconsistencies and data anomalies.
- Security Issue: If foreign key relationships are not properly secured, unauthorized users might manipulate related tables, potentially leading to data breaches or unauthorized access.
- Availability Issue: If the referenced table becomes unavailable, the foreign key constraints might prevent access to the referencing table, impacting system availability.
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NOT NULL Constraint:
- Data Integrity Issue: If a required field is allowed to be NULL, it can lead to incomplete or inaccurate data. This can affect data analysis and reporting.
- Security Issue: If critical fields are allowed to be NULL, it might create vulnerabilities for data manipulation or bypassing security checks.
- Availability Issue: While not directly related to availability, data that is missing because of lack of a NOT NULL constraint can cause application errors, which can affect application uptime.
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Unique Constraint:
- Data Integrity Issue: Violations of the unique constraint can result in duplicate entries for fields that should be unique, leading to data inconsistencies and making it difficult to maintain data accuracy.
- Security Issue: If unique constraints are not properly enforced, attackers might exploit vulnerabilities to insert duplicate records, potentially leading to data corruption or unauthorized access.
- Availability Issue: If the unique index becomes corrupted or inefficient, it can slow down data retrieval and insertion operations, impacting system performance and availability.
Part 2)
The normalization process is crucial for maintaining data integrity, security, and availability in relational databases. By structuring data to minimize redundancy and dependencies, we reduce the risk of anomalies and improve database performance.
- Data Integrity: Normalization helps prevent data anomalies, such as insertion, update, and deletion anomalies. For example, in a "Parts and Suppliers" scenario, without proper normalization, updating a supplier's address might require updating multiple records, potentially leading to inconsistencies. Normalization ensures that supplier information is stored in a separate table, preventing such anomalies.
- Security: Normalization can enhance security by reducing data redundancy and simplifying access control. By separating sensitive data into distinct tables, we can implement granular access controls, limiting exposure to unauthorized users. For instance, supplier financial information can be stored in a separate table with restricted access.
- Availability: Normalization can improve database performance and availability. By reducing data redundancy and optimizing data storage, we minimize the amount of data that needs to be processed, leading to faster query execution and improved system responsiveness. Additionally, normalized databases are easier to maintain, which helps to ensure that the system remains available and reliable. For instance, if supplier information is stored in a normalized fashion, and a server fails, the database can be restored more quickly and efficiently.