Test about database security P11
Testing of databases will help you gain more useful knowledge about this topic to apply to learning and working. The question set will have 10 sentences to test your knowledge.
Question 1. Value of the components of the specified key:
Cannot get null values or unknown values
Can get null values or unknown values
Cannot get null value but can get unknown values
Question 2. Key attributes are:
Properties are not contained in the key
Question 3. The goal of the database is:
Reflect honestly the real world data
The independence of the data
Question 4. The separation process does not cause loss of information in the sense of:
The original relationship is restored from projection relations by natural connection magic
The original relationship is restored correctly from projection relationships
The original relationship is restored from projection relationships by connection magic
The original relationship is restored from the relations projected by projection and selected
Question 5. φ [Ω1, Ω2 ., Ωp] is the separation - the natural connection of the relational schema if:
Naturally connecting projection relationships
φ [Ω1, Ω2, ., Ωp] is a separation and connection of projection relationships
φ [Ω1, Ω2, ., Ωp] is a separation and natural connection of projection relations
Connection of projection relations
Question 6. φ [Ω1, Ω2, ., Ωp] is a separation without loss of information, if:
The result of natural connection of projection relationships containing the original relationship.
The result of the natural connection of the main relationships is the original relationship.
The result of natural connection of projection relationships is contained in the original relationship.
The result of connecting relationships is shown on some properties of the original relationship.
Question 7. The objective of separating the relational schema is:
In order to optimize queries
In order to eliminate information anomalies when performing storage operations
Question 8. It is necessary to standardize data because:
Key value receives null value or unknown value
When performing storage operations on non-standardized relations, information anomalies often appear
When performing separation - connect the relationships automatically
When performing searches, there are information anomalies
Question 9. Information anomaly is the cause:
Obstructing updating and supplementing information
Obstructing the separation of information loss
Obstructing the search and inquiry
Obstructing the implementation of archives
Question 10. The objective of data normalization is:
Highest level of possibility of occurrence of information anomalies
Guaranteed for data storage