Database Systems Fundamentals
Due to which of the following actions does a checkpoint record in the log also include additional information, and this can facilitate undoing transaction operations in the event that a transaction must be rolled back? A. Force-write all main memory buffers that have been modified to disk. B. Resume executing transactions. C. Write a record to the log, and force-write the log to disk. D. Suspend execution of transactions temporarily.
A
What problems occur due to the redundancy in storing the same data multiple times? Each correct answer represents a complete solution. Choose all that apply. A. Duplication of effort B. Wastage of storage space C. Inconsistency D. Loss of availability
ABC
Which of the following are steps of ER-to-relational mapping algorithm? Each correct answer represents a complete solution. Choose all that apply. A. Mapping of binary 1:1 relationship types B. Mapping of weak entity types C. Mapping of regular entity types D. Mapping of N-ary relationship types E. Mapping of single-valued attributes
ABCD
In which of the following categories do the physical design decisions for indexing fall? Each correct answer represents a complete solution. Choose all that apply. A. Whether to set up a clustered index B. Whether to use a hash index over a tree index C. Whether to use linear hashing for a file D. Whether to index an attribute E. What attribute or attributes to index on
ABDE
Which of the following constraints are possible constraints on a specialization? Each correct answer represents a complete solution. Choose all that apply. A. Overlapping, total B. Joint, partial C. Disjoint, total D. Overlapping, partial
ACD
Which of the following interpretations are true of NULLs? Each correct answer represents a complete solution. Choose all that apply. A. The value is known but absent; that is, it has not been recorded yet. B. The value is absent but it is recorded. C. The attribute value for the tuple is unknown. D. The attribute does not apply to the tuple.
ACD
Which of the following types of actions are used to control discretionary database authorization? Each correct answer represents a complete solution. Choose all that apply. A. Privilege granting B. Security level assignment C. Account creation D. Privilege revocation
AD
Which of the following constraints can be directly expressed in the schemas of the data model? Each correct answer represents a complete solution. Choose all that apply. A. State B. Entity integrity C. Key D. Domain
BCD
Which of the following multiset operations do not eliminate duplicates? Each correct answer represents a complete solution. Choose all that apply. A. UNION B. INTERSECT ALL C. EXCEPT ALL D. UNION ALL
BCD
What are the NOSQL characteristics related to distributed databases and distributed systems? Each correct answer represents a complete solution. Choose all that apply. A. Versioning B. High-performance data access C. Sharding of files D. Replication models E. Scalability
BCDE
Which of the following associations is represented as a line connecting the participating classes, and may optionally have a name? Qualified Unidirectional Binary Reflexive
Binary
Which of the following techniques to make accessing data more efficient on HDDs deals with the incompatibility of speeds between a CPU and the electromechanical device? Buffering of data Use of log disks Proper organization of data on disk Reading data ahead of request
Buffering of data
Which of the following is described in the given statement? "Take immediate action to eliminate the attacker's access to the system and to isolate or contain the problem to prevent further spread." ReconfiguratioN Fault treatment Confinement Damage assessment
Confinement
Which type of XML document is formatted as XML document in order to exchange it over the Web? Hybrid XML Data-centric Document-centric
Data-centric
Who communicates with all prospective database users to understand their requirements and to create a design that meets those requirements? Database administrator Database designer Application programmer System analyst
Database designer
Which of the following clauses assigns a variable to range over each of the individual elements in a sequence? RETURN FOR WHERE ORDER BY
FOR
Consider the first step involved in acquisition of data for warehouse: "Extract data from multiple and heterogeneous sources." Which of the following steps will be the second step involved in acquisition of data for warehouse? Format data for consistency within a warehouse. Load the data into the warehouse. Represent data in the data model of the warehouse. Clean data to ensure validity.
Format data for consistency within a warehouse.
Which of the following operations takes the results of two queries and returns only those rows that appear in both result sets without eliminating duplicates? UNION EXCEPT ALL INTERSECT ALL UNION ALL
INTERSECT ALL
Which abstraction concept is needed to distinguish among database objects and classes, and to identify database objects? Specialization Identification Aggregation Classification
Identification
Which of the following strategies updates a view as soon as the base tables are changed? Immediate update Periodic update Lazy update
Immediate update
What challenges are faced by big data technologies when they are used for analytics applications? Each correct answer represents a complete solution. Choose all that apply. Inconsistent and incomplete information Privacy and confidentiality Heterogeneity of information Fault tolerance
Inconsistent and incomplete information, Privacy and confidentiality, Heterogeneity of information
Which of the following properties is enforced by the concurrency control subsystem of the DBMS? Atomicity Consistency preservation Durability Isolation
Isolation
Which of the following updates recomputes a view only upon demand? Lazy Immediate Periodic
Lazy
Which stage of a distributed database query is performed locally? Localization Local query optimization Global query optimization Query mapping
Local query optimization
Which spatial operator provides a more specific description of the object's geometry and measures some global properties of single objects? Metric Projective Topological Dynamic
Metric
Which of the following methods are used for collision resolution? Each correct answer represents a complete solution. Choose all that apply. Folding Multiple hashing Chaining Open addressing
Multiple hashing Chaining Open addressing
Consider the following skills of a surgical technician: Ability to work in groups Possesses a calm nature Excellent communication skills Willingness to learn The skills of a surgical technician are an example of which type of attribute? Multivalued attribute Derived attribute Composite attribute Atomic attribute
Multivalued attribute
Which of the following functions does SQL allow to be blocked from public use, and an EXECUTE privilege is needed to have access to these functions? Mutator CARDINALITY Constructor Observer
Mutator, Constructor , Observer
What term is used for intermediate form of databases before they are cleansed, aggregated, and transformed into a data warehouse? DSS OLAP ODS OLTP
ODS
Consider the following options for mapping specialization or generalization: Option 1: Multiple relations—superclass and subclasses Option 2: Multiple relations—subclass relations only Option 3: Single relation with one type attribute Option 4: Single relation with multiple type attributes Which of the following options works for any constraints on the specialization, i.e., disjoint or overlapping, total or partial? Option 1 Option 2 Option 3 Option 4
Option 1
Which of the following violations will occur when a transaction may read a set of rows from a table, based on some condition specified in the SQL WHERE-clause? Nonrepeatable read Phantom Dirty read
Phantom
At which of the following levels is the actual data stored in a database? Physical External Conceptual Internal
Physical
Which of the following indexes requires that the ordering field of the data file has a distinct value for each record as well as records are of fixed length with two fields? Clustering Secondary Primary
Primary
Which operation is used for inserting new data or new versions of existing data items? Scan Create Put Get
Put
Which of the following rules states that a set of attributes always determines itself or any of its subsets? Decomposition Transitive Augmentation Reflexive
Reflexive
During which of the following steps do the database designers interview prospective database users to understand and document their data necessities? Requirements collection and analysis Physical design Logical design Conceptual design
Requirements collection and analysis
Which type of end user tries to learn most of the DBMS facilities to achieve their complex requirements? This task contains the radio buttons and checkboxes for options. Sophisticated Casual Naive Standalone
Sophisticated
Consider the following example: "The salary of an employee should not exceed the salary of the employee's supervisor." Which of the following constraints is suitable for the given example? Domain Entity integrity Transition Referential integrity
Transition
Which of the following functional dependencies occurs only in a relation that contains three or more attributes and an attribute is indirectly dependent on another attribute that is not part of the primary key? Partial Transitive Multivalued
Transitive
Which statistical model provides a framework in which term weighting, ranking of retrieved documents, and determining the relevance of feedback are possible? Semantic Vector space Boolean Probabilistic
Vector space
Consider the following statement: "If the validation phase is successful, the transaction updates are applied to the database; otherwise, the updates are discarded and the transaction is restarted." In which of the following phases of concurrency control protocol does this happen? Read Write Validation
Write