Database Chapters 4,5,7 Midterm 2 Quiz
Practice for midterm 2
Questions and Answers
- 1.
CH -4 A nonkey attribute is also called a(n)
- A.
Column
- B.
Unimportant datum
- C.
Descriptor
- D.
Address
Correct Answer
C. DescriptorExplanation
A nonkey attribute is also called a descriptor because it provides additional information about an entity but does not play a role in identifying or distinguishing that entity. It is not a critical piece of data in the database and does not contribute to the primary key or any unique identifier. Instead, it helps to describe or provide details about the entity.Rate this question:
-
- 2.
A primary key whose value is unique across all relations is called a(n):
- A.
Global primary key
- B.
Inter-table primary key
- C.
Enterprise key
- D.
Foreign global key
Correct Answer
C. Enterprise keyExplanation
An enterprise key is a primary key that is unique across all relations in a database. This means that no other relation within the database can have the same value for this key. It is used to uniquely identify records across multiple tables in the entire enterprise system. This ensures data integrity and consistency throughout the database, allowing for efficient data retrieval and manipulation.Rate this question:
-
- 3.
An attribute that may have more than one meaning is called a(n):
- A.
Homonym
- B.
Alias
- C.
Double defined attribute
- D.
synonym
Correct Answer
A. HomonymExplanation
A homonym is a word that has multiple meanings. In the context of this question, an attribute that may have more than one meaning is referred to as a homonym. This means that the attribute can be interpreted or understood in different ways, leading to potential confusion or ambiguity.Rate this question:
-
- 4.
Two or more attributes having different names but the same meaning are called:
- A.
Homonyms
- B.
Aliases
- C.
Synonyms
- D.
Alternate attributes
Correct Answer
C. SynonymsExplanation
Synonyms are two or more attributes that have different names but the same meaning. In other words, they are different terms used to describe the same concept or attribute. For example, "car" and "automobile" are synonyms as they both refer to the same object. Similarly, in the context of databases, synonyms can be used to refer to different attribute names that represent the same underlying data.Rate this question:
-
- 5.
An understanding of how to merge relation is important because:
- A.
A) there may be a need to merge relations on projects with subteams
- B.
Different views may be integrated
- C.
New data requirements may produce new relations to be merged
- D.
All of the above
Correct Answer
D. All of the aboveExplanation
An understanding of how to merge relations is important because there may be a need to merge relations on projects with subteams, different views may need to be integrated, and new data requirements may produce new relations that need to be merged.Rate this question:
-
- 6.
Which of the following anomalies result from a transitive dependency?
- A.
Insertion
- B.
Modification
- C.
Deletion
- D.
All of the above
Correct Answer
D. All of the aboveExplanation
A transitive dependency is a relationship between three or more attributes in a database table, where the value of one attribute determines the value of another attribute indirectly. In this case, all of the given anomalies (insertion, modification, and deletion) can occur as a result of a transitive dependency. When a transitive dependency exists, inserting, modifying, or deleting a value in one attribute can cause inconsistencies or errors in the related attributes. Therefore, all of the mentioned anomalies can be caused by a transitive dependency.Rate this question:
-
- 7.
When the value of one attribute (the determinant) determines the value of another attribute, it is called:
- A.
Functional dependency
- B.
Merged relation
- C.
Transitive dependency
- D.
Full dependency
Correct Answer
A. Functional dependencyExplanation
Functional dependency refers to a situation where the value of one attribute determines the value of another attribute. In other words, if we know the value of one attribute, we can determine the value of another attribute based on that. This concept is important in database design and normalization, as it helps to ensure data integrity and eliminate redundancy. Therefore, the correct answer is functional dependency.Rate this question:
-
- 8.
A candidate key must satisfy all of the following conditions EXCEPT:
- A.
The key must uniquely identify the row
- B.
The key must indicate the rows position in the table
- C.
The key must be nonredundant
- D.
Each nonkey attribute is functionally dependent upon it
Correct Answer
B. The key must indicate the rows position in the tableExplanation
A candidate key is a unique identifier for a row in a table. It must satisfy the conditions of being nonredundant, ensuring that each nonkey attribute is functionally dependent upon it, and uniquely identifying the row. However, it does not need to indicate the row's position in the table. The position of a row in a table is typically determined by the order in which it was inserted, but it is not a requirement for a candidate key.Rate this question:
-
- 9.
A constraint between two attributes is called a(n):
- A.
Functional relation
- B.
Attribute dependency
- C.
Functional dependency
- D.
Functional relation constraint
Correct Answer
C. Functional dependencyExplanation
A constraint between two attributes is called a functional dependency. This means that one attribute's value is determined by another attribute's value. In other words, if you know the value of one attribute, you can determine the value of the other attribute. This constraint helps maintain data integrity and ensures that the database remains consistent.Rate this question:
-
- 10.
A relation that contains no multivalued attributes, and has nonkey attributes solely dependent on the primary key, but contains transitive dependencies is in which normal form?
- A.
First
- B.
Second
- C.
Third
- D.
Fourth
Correct Answer
B. SecondExplanation
The given question is asking about the normal form of a relation that has no multivalued attributes, nonkey attributes solely dependent on the primary key, but contains transitive dependencies. The correct answer is "Second." Second normal form (2NF) states that a relation should be in first normal form (1NF) and all nonkey attributes should be fully dependent on the primary key. In this case, the relation meets the criteria for 2NF because it has no multivalued attributes and the nonkey attributes are solely dependent on the primary key. However, it still contains transitive dependencies, which means that some nonkey attributes are dependent on other nonkey attributes.Rate this question:
-
- 11.
When all multivalued attributes have been removed from a relation , it is said to be in:
- A.
First normal form
- B.
Second normal form
- C.
Boyce-Codd normal form
- D.
Third normal form
Correct Answer
A. First normal formExplanation
When all multivalued attributes have been removed from a relation, it is said to be in the first normal form. This means that each attribute in the relation contains only atomic values, and there are no repeating groups or arrays of values within a single attribute. The first normal form is the basic level of normalization and ensures that the relation is free from redundancy and anomalies.Rate this question:
-
- 12.
All of the following are the main goals of normalization EXCEPT:
- A.
Minimize data redundancy
- B.
Simplify the enforcement of referential integrity
- C.
Maximize storage space
- D.
Make it easier to maintain data
Correct Answer
C. Maximize storage spaceExplanation
Normalization is a database design technique that aims to minimize data redundancy and improve data integrity. It simplifies the enforcement of referential integrity by ensuring that relationships between tables are properly defined and maintained. It also makes it easier to maintain data by organizing it into smaller, more manageable tables. However, maximizing storage space is not a goal of normalization. Instead, normalization focuses on optimizing data structure and reducing duplication to improve efficiency and maintainability.Rate this question:
-
- 13.
If foreign key is referenced to the primary key in the same relation, we call it:
- A.
Primary
- B.
Recursive primary
- C.
Composite
- D.
Recursive foreign
Correct Answer
D. Recursive foreignExplanation
If a foreign key is referenced to the primary key in the same relation, it is called a recursive foreign key. This means that the foreign key is pointing back to the same table and is used to establish a relationship between different rows within the same table. This can be useful in scenarios where there is a hierarchical or recursive relationship between entities in the table.Rate this question:
-
- 14.
When a regular entity type contains a multivalued attribute, one must:
- A.
Create a single relation with multiple lines for each instance of the multivalued attribute
- B.
Create two new relations, one containing the multivalued attribute
- C.
Create two new relations, both containing the multivalued attribute
- D.
None of the above
Correct Answer
B. Create two new relations, one containing the multivalued attributeExplanation
When a regular entity type contains a multivalued attribute, creating two new relations, one containing the multivalued attribute, is the correct approach. This is because a multivalued attribute cannot be represented in a single relation with multiple lines for each instance of the attribute. Instead, it requires a separate relation to properly capture the multiple values. Therefore, the option of creating two new relations, one containing the multivalued attribute, is the appropriate solution in this scenario.Rate this question:
-
- 15.
A relation that contains minimal redundancy and allows easy use is considered to be:
- A.
Clean
- B.
simple
- C.
Complex
- D.
Well structured
Correct Answer
D. Well structuredExplanation
A relation that is well structured means that it is organized and designed in a way that minimizes redundancy, meaning that there is no unnecessary repetition of data. It also implies that the relation is easy to use and navigate, making it user-friendly. Therefore, a well-structured relation is the one that contains minimal redundancy and allows easy use.Rate this question:
-
- 16.
Which of the following are anomalies that can be caused by redundancies in tables
- A.
Insertion
- B.
Deletion
- C.
Modification
- D.
All of the above
Correct Answer
D. All of the aboveExplanation
Redundancies in tables can lead to anomalies such as insertion anomalies, deletion anomalies, and modification anomalies. Insertion anomalies occur when it is not possible to insert certain data into the table without also inserting unrelated data. Deletion anomalies occur when deleting certain data also results in the unintentional loss of other related data. Modification anomalies occur when updating certain data requires making changes in multiple places, leading to inconsistencies. Therefore, all of the options mentioned (insertion, deletion, and modification) can be caused by redundancies in tables.Rate this question:
-
- 17.
The __________ states that no primary key attribute may be null
- A.
Referential integrity constraint
- B.
Entity integrity rule
- C.
Partial specialization rule
- D.
Range domain rule
Correct Answer
B. Entity integrity ruleExplanation
The entity integrity rule states that no primary key attribute may be null. This means that every entity in a table must have a unique identifier (primary key) and this identifier cannot have a null value. This rule ensures that each entity in a table is uniquely identified and helps maintain the integrity and consistency of the data.Rate this question:
-
- 18.
A rule that states that each foreign key value must match a primary key value in the other
- A.
Referential integrity constraint
- B.
Key match rule
- C.
Entity key group rule
- D.
Foreign/primary match rule
Correct Answer
A. Referential integrity constraintExplanation
The explanation for the correct answer is that a referential integrity constraint is a rule that ensures that each foreign key value in a table must match a primary key value in another table. This constraint helps maintain the integrity and consistency of the data by preventing orphaned records or invalid references. It enforces the relationship between tables and ensures that the data remains accurate and valid.Rate this question:
-
- 19.
A domain definition consists of the following components EXCEPT:
- A.
Domain name
- B.
Data type
- C.
Integrity constraint
- D.
size
Correct Answer
C. Integrity constraintExplanation
A domain definition consists of the domain name, data type, and size. The integrity constraint is not a component of a domain definition. Integrity constraints are rules or conditions that are applied to the data within a domain to ensure its accuracy and consistency. They are separate from the domain definition itself, which primarily defines the characteristics and properties of the data within a domain.Rate this question:
-
- 20.
The entity integrity rule states that:
- A.
No primary key attribute can be null
- B.
Referential integrity must be maintained across all entities
- C.
Each entity must have a primary key
- D.
A primary key must have only one attribute
Correct Answer
A. No primary key attribute can be nullExplanation
The entity integrity rule states that no primary key attribute can be null. This means that every entity in a database must have a primary key, and this primary key cannot have a null value. The primary key is used to uniquely identify each record in a table, and having a null primary key would mean that the record cannot be uniquely identified. Therefore, it is essential to ensure that the primary key attribute is always populated with a non-null value.Rate this question:
-
- 21.
Which of the following are properties of relations
- A.
Each attribute has a unique name
- B.
No two rows in a relation are identical
- C.
There are no multivalued attributes are in a relation
- D.
All of the above
Correct Answer
D. All of the aboveExplanation
All of the given options are properties of relations. In a relation, each attribute must have a unique name to identify it uniquely. Additionally, no two rows in a relation can be identical, as each row represents a unique tuple. Lastly, relations in a database do not allow multivalued attributes, meaning that each attribute in a relation can have only a single value. Therefore, all of the given options are correct properties of relations.Rate this question:
-
- 22.
A primary key that consists of more than one attribute is called a:
- A.
Foreign key
- B.
Composite key
- C.
Multivalued key
- D.
Cardinal key
Correct Answer
B. Composite keyExplanation
A primary key that consists of more than one attribute is called a composite key. This means that the primary key is made up of multiple columns in a table, rather than just a single column. Using a composite key allows for a more precise and unique way of identifying records in a table, as it takes into account multiple attributes to create a unique identifier.Rate this question:
-
- 23.
An attribute in a relation of a database that serves as the primary key of another relation in the same database is called a:
- A.
Link attribute
- B.
Link key
- C.
Foreign key
- D.
Foreign attribute
Correct Answer
C. Foreign keyExplanation
A foreign key is an attribute in a relation of a database that serves as the primary key of another relation in the same database. It is used to establish a relationship between two tables in a database by referencing the primary key of one table as a foreign key in another table. This allows for the creation of a link between the two tables and enables the enforcement of referential integrity, ensuring that the data in the foreign key column matches the data in the primary key column it references.Rate this question:
-
- 24.
An attribute (or attributes) that uniquely identifies each row in a relation is called a:
- A.
Column
- B.
Foreign field
- C.
Primary key
- D.
Duplicate key
Correct Answer
C. Primary keyExplanation
A primary key is an attribute or set of attributes that uniquely identifies each row in a relation. It ensures that there are no duplicate values in the primary key column(s) and provides a way to uniquely identify and access each row in the table. This is essential for maintaining data integrity and for establishing relationships between tables in a database.Rate this question:
-
- 25.
________________ is a component of the relational data model included to specify business rules to maintain the integrity of data when they are manipulated.
- A.
Business rule constraint
- B.
Data integrity
- C.
Business integrity
- D.
Data structure
Correct Answer
B. Data integrityExplanation
Data integrity is a component of the relational data model that ensures the accuracy, consistency, and reliability of data. It specifies the rules and constraints that need to be followed when manipulating data to maintain its integrity. These rules can include constraints such as primary key uniqueness, foreign key relationships, and data validation rules. By enforcing data integrity, organizations can ensure that their data remains reliable and consistent, thereby improving the overall quality and trustworthiness of their data.Rate this question:
-
- 26.
A two-dimensional table of data is called a:
- A.
group
- B.
set
- C.
declaration
- D.
Relation
Correct Answer
D. RelationExplanation
A two-dimensional table of data is commonly referred to as a "relation" in the field of database management. This term is used to describe the organization and structure of data in a tabular format, where each row represents a record and each column represents a specific attribute or field. The use of the term "relation" emphasizes the interconnectedness and interdependence of the data within the table, highlighting the ability to establish relationships and perform operations such as joins and queries.Rate this question:
-
- 27.
The relational data model consists of which components?
- A.
Data structure
- B.
Data manipulation
- C.
Data integrity
- D.
All of the above
Correct Answer
D. All of the aboveExplanation
The relational data model consists of all of the mentioned components: data structure, data manipulation, and data integrity. Data structure refers to the organization and format of the data stored in tables. Data manipulation involves operations such as inserting, updating, and deleting data in the tables. Data integrity ensures that the data is accurate, consistent, and follows predefined rules or constraints. Therefore, all of these components are essential in the relational data model.Rate this question:
-
- 28.
Physical database design decisions must be made carefully because of impacts on:
- A.
Data accessibility
- B.
Response times
- C.
Security
- D.
All of the above
Correct Answer
D. All of the aboveExplanation
Physical database design decisions must be made carefully because they have impacts on data accessibility, response times, and security. Data accessibility refers to the ability to retrieve and manipulate data efficiently, which can be affected by the physical design choices. Response times, or the speed at which the database responds to user queries, can also be influenced by the physical design. Additionally, security measures such as encryption, access controls, and backup strategies must be considered during the physical design process to protect the data from unauthorized access or loss. Therefore, all of the mentioned factors are impacted by physical database design decisions.Rate this question:
-
- 29.
LAST CH 4 A form of database specification that indicates all the parameters for data storage that are then input to database implementation is:
- A.
Logical
- B.
Physical
- C.
Schematic
- D.
conceptual
Correct Answer
B. PhysicalExplanation
The correct answer is "physical". In database specification, the physical level focuses on the actual implementation of the database and includes details such as file organization, indexing methods, and storage structures. It specifies how the data is physically stored on the storage medium. Logical and conceptual levels deal with the logical organization and structure of the database, while the schematic level focuses on the design and organization of individual database components.Rate this question:
-
- 30.
START CH5 - A method to allow adjacent secondary memory space to contain rows from several tables is called:
- A.
Cluttering
- B.
Clustering
- C.
Concatenating
- D.
Compiling
Correct Answer
B. ClusteringExplanation
Clustering is a method that allows adjacent secondary memory space to contain rows from several tables. It involves grouping similar data together based on certain criteria, such as common attributes or values. This helps improve data retrieval and processing efficiency by reducing the need to access multiple locations in secondary memory. Clustering can be particularly beneficial in database management systems where tables with related data can be physically stored close to each other, resulting in faster query execution and improved performance.Rate this question:
-
- 31.
A file organization that uses hashing to map a key into a location in an index where there is a pointer to the actual data record matching the hash key is called a:
- A.
Hashed file organization
- B.
Hash key
- C.
Multi-indexed file organization
- D.
Hash index table
Correct Answer
D. Hash index tableExplanation
A file organization that uses hashing to map a key into a location in an index where there is a pointer to the actual data record matching the hash key is called a hash index table. This type of file organization utilizes a hash function to generate a unique index for each key, allowing for efficient retrieval of data records by directly accessing the index table. The index table contains pointers to the actual data records, enabling quick and direct access to the desired data based on the hash key.Rate this question:
-
- 32.
In which type of file is multiple key retrieval not possible
- A.
Hashed
- B.
Other options werent in PDF
Correct Answer
A. HashedExplanation
Multiple key retrieval is not possible in a hashed file. In a hashed file, the keys are mapped to specific locations using a hash function. This allows for quick access to individual records based on their keys. However, since the keys are transformed into specific locations, it becomes difficult to retrieve multiple keys simultaneously. In other types of files, such as indexed or sequential files, it is possible to retrieve multiple keys efficiently.Rate this question:
-
- 33.
A(n) _______________ is a routine that converts a primary key value into a relative record number.
- A.
Record index calculator
- B.
Index pointer program
- C.
Hashing algorithm
- D.
Pointing algorithm
Correct Answer
C. Hashing algorithmExplanation
A hashing algorithm is a routine that converts a primary key value into a relative record number. It uses a mathematical function to map the key value to a specific location in a data structure, such as a hash table. This allows for efficient retrieval and storage of records based on their primary key values.Rate this question:
-
- 34.
An index of columns from two or more tables that come from the same domain of values is called a:
- A.
Bitmap index
- B.
Multivalued index
- C.
Join index
- D.
Transaction index
Correct Answer
C. Join indexExplanation
A join index is an index that is created on columns from multiple tables that belong to the same domain of values. It is used to improve the performance of queries that involve joining these tables. By creating a join index, the database can precompute the join operation and store the results in the index, allowing for faster retrieval of data when executing queries that involve joining these tables.Rate this question:
-
- 35.
One field or combination of fields for which more than one record may have the same combination of values is called a(n):
- A.
Secondary key
- B.
Index
- C.
Composite key
- D.
Linked key
Correct Answer
A. Secondary keyExplanation
A secondary key is a field or combination of fields in a database table that allows more than one record to have the same combination of values. It is used to provide an alternate way to uniquely identify records in addition to the primary key. This can be useful in situations where there is a need to efficiently search and retrieve data based on criteria other than the primary key.Rate this question:
-
- 36.
A(n) _______________ is a technique for physically arranging the records of a file on secondary storage devices
- A.
Physical pointer
- B.
Retrieval program
- C.
File organization
- D.
Update program
Correct Answer
C. File organizationExplanation
File organization refers to the technique of arranging the records of a file on secondary storage devices. It determines how the data is stored, accessed, and retrieved from the file. Different file organization methods include sequential, indexed, and hashed. Each method has its own advantages and disadvantages, depending on the specific requirements of the application. Therefore, file organization plays a crucial role in optimizing data storage and retrieval efficiency.Rate this question:
-
- 37.
A(n) __________ is a field of data used to locate a related field or record
- A.
Key
- B.
Index
- C.
Lock
- D.
Pointer
Correct Answer
D. PointerExplanation
A pointer is a field of data used to locate a related field or record. Pointers are commonly used in programming to store memory addresses of other variables or objects. By storing the memory address of a related field or record in a pointer, it becomes easier and more efficient to access and manipulate the data. Pointers essentially "point" to the location of the data, allowing for quick and direct access.Rate this question:
-
- 38.
A contiguous section of disk storage space is called a(n):
- A.
Track
- B.
Sector
- C.
Extent
- D.
Tablespace
Correct Answer
C. ExtentExplanation
An extent is a contiguous section of disk storage space. It is a range of consecutive blocks allocated to a file or database object. Extents are used to efficiently allocate and manage disk space, as they reduce fragmentation and improve I/O performance. Therefore, an extent is the correct term for a contiguous section of disk storage space.Rate this question:
-
- 39.
While Oracle has responsibility for managing data inside a tablespace, the tablespace as a while is managed by the:
- A.
User
- B.
Database administrator
- C.
Application developer
- D.
Operating system
Correct Answer
D. Operating systemExplanation
The operating system is responsible for managing the tablespace as a whole. Although Oracle is responsible for managing the data inside the tablespace, the overall management and control of the tablespace is handled by the operating system. This includes tasks such as allocating and deallocating space, managing file systems, and performing backup and recovery operations. The user, database administrator, and application developer have specific roles and responsibilities within the Oracle database, but they do not directly manage the tablespace at the operating system level.Rate this question:
-
- 40.
Within Oracle, the named set of storage elements in which physical files for database tables may be stored is called a(n):
- A.
Extent
- B.
Table
- C.
Tablespace
- D.
Partition
Correct Answer
C. TablespaceExplanation
A tablespace in Oracle is a named set of storage elements where physical files for database tables can be stored. It provides a logical structure for organizing and managing database objects, such as tables, indexes, and partitions. By allocating space within a tablespace, Oracle can efficiently manage the storage and retrieval of data. Multiple tablespaces can be created within a database, allowing for better control over storage allocation and performance optimization.Rate this question:
-
- 41.
Another form of demornalization where the same data are stored in multiple places in the database is called:
- A.
Data duplication
- B.
Data replication
- C.
Advanced placement
- D.
Horizaontal partitioning
Correct Answer
B. Data replicationExplanation
Data replication refers to the practice of storing the same data in multiple places within a database. This is done to improve data availability, reliability, and performance. By duplicating data, it becomes possible to access it from different locations, reducing the risk of data loss and ensuring that the system can continue to function even if one copy of the data becomes unavailable. Data replication is commonly used in distributed databases and systems that require high levels of data availability and fault tolerance.Rate this question:
-
- 42.
All of the following are horizontal partitioning methods in Oracle EXCEPT:
- A.
Key range partitioning
- B.
Hash partitioning
- C.
Multivalued partitioning
- D.
Composite partitioning
Correct Answer
C. Multivalued partitioningExplanation
Multivalued partitioning is not a horizontal partitioning method in Oracle. Horizontal partitioning is a technique used to divide a table into multiple smaller tables based on a specific criterion, such as a range of values or a hash function. Key range partitioning divides the table based on a specified range of key values, hash partitioning distributes the data based on a hash function, and composite partitioning combines multiple partitioning methods. However, multivalued partitioning is not a recognized technique in Oracle for horizontal partitioning.Rate this question:
-
- 43.
One disadvantage of partitioning is:
- A.
Simplicity
- B.
Remote optimization
- C.
Extra space and update time
- D.
Shorter technology spans
Correct Answer
C. Extra space and update timeExplanation
Partitioning in this context refers to dividing a system or database into smaller sections or partitions. One disadvantage of partitioning is that it requires extra space and update time. Partitioning involves creating separate storage spaces for different partitions, which can lead to increased storage requirements. Additionally, when updates or changes are made to the system, it may take longer to update each partition individually, resulting in increased update time. Therefore, the extra space and update time required are considered as a disadvantage of partitioning.Rate this question:
-
- 44.
One advantage of partitioning is:
- A.
Efficiency
- B.
Remote optimization
- C.
Extra space and update time
- D.
Both A and B
Correct Answer
A. EfficiencyExplanation
Partitioning provides the advantage of efficiency. By dividing a larger problem or dataset into smaller, more manageable parts, partitioning allows for parallel processing and distributed computing. This can significantly improve the overall efficiency of a system or algorithm, as multiple tasks can be executed simultaneously. Additionally, partitioning can help optimize remote operations, as data can be distributed across different nodes or servers, reducing network latency and improving performance. Therefore, the correct answer is efficiency.Rate this question:
-
- 45.
Horizontal partitioning makes sense:
- A.
When different categories of a table's rows are processed seperately
- B.
When less security is needed
- C.
When partitions must be orgranized the same
- D.
When all of the above are true
Correct Answer
A. When different categories of a table's rows are processed seperatelyExplanation
Horizontal partitioning makes sense when different categories of a table's rows are processed separately. This means that the rows of the table are divided into separate partitions based on specific categories or criteria. By doing so, it becomes easier to perform operations or queries on specific categories of data without affecting the entire table. This can improve performance and efficiency in situations where different categories of data require different processing or analysis.Rate this question:
-
- 46.
Distributing the rows of data into separate files is called:
- A.
Normalization
- B.
Horizontal partitioning
- C.
Vertical partitioning
- D.
File allocation
Correct Answer
B. Horizontal partitioningExplanation
Horizontal partitioning is the correct answer because it refers to the process of distributing rows of data into separate files. This technique is commonly used in database management systems to improve performance and scalability. By dividing the data horizontally, each partition can be stored and processed independently, allowing for parallel processing and reducing the load on individual servers. Horizontal partitioning is especially useful in scenarios where the dataset is too large to fit on a single server or when different parts of the data need to be accessed or modified separately.Rate this question:
-
- 47.
All of the following are common denormalization opportunities EXCEPT:
- A.
Two entities with a one-to-one relationship
- B.
A one-to-many relationship
- C.
A many-to-many relationship with nonkey attributes
- D.
Reference data
Correct Answer
B. A one-to-many relationshipExplanation
Denormalization is a technique used in database design to improve performance by adding redundant data to eliminate the need for complex joins. In a one-to-many relationship, there is already a natural redundancy as the "one" side can be repeated multiple times in the "many" side. Therefore, denormalizing this relationship would not provide any additional benefits. However, in a one-to-one relationship, a many-to-many relationship with nonkey attributes, or with reference data, denormalization can be beneficial as it can reduce the number of joins required and improve query performance.Rate this question:
-
- 48.
Sensitivity testing involves:
- A.
Checking if data is allergic
- B.
Seeing how accurate data are
- C.
Checking to see if missing data will greatly impact results
- D.
None of the above
Correct Answer
C. Checking to see if missing data will greatly impact resultsExplanation
Sensitivity testing involves checking to see if missing data will greatly impact results. This means that sensitivity testing is done to assess the impact of missing data on the accuracy and reliability of the results. By conducting sensitivity testing, researchers can determine the extent to which missing data can affect the validity of the findings and make necessary adjustments or considerations to ensure the accuracy of the analysis.Rate this question:
-
- 49.
A method for handling missing data is to:
- A.
Substitute and estimate for the missing data
- B.
Track missing data with special reports
- C.
Perform sensitivity testing
- D.
All of the above
Correct Answer
D. All of the aboveExplanation
The correct answer is "all of the above" because each of the options mentioned - substituting and estimating for the missing data, tracking missing data with special reports, and performing sensitivity testing - are valid methods for handling missing data. By using a combination of these approaches, one can effectively address the issue of missing data and ensure that it does not significantly impact the overall analysis or results.Rate this question:
-
- 50.
In which data model would a code table appear
- A.
Conceptual
- B.
Logical
- C.
Physical
- D.
Data layout
Correct Answer
C. PhysicalExplanation
A code table would appear in the physical data model. The physical data model represents the actual implementation of the database and includes details such as data types, indexes, and storage structures. Code tables are used to store codes or values that are frequently used in the database, such as status codes or category codes. They provide a standardized and efficient way to store and retrieve these values, making them an important component of the physical data model.Rate this question:
-
Quiz Review Timeline +
Our quizzes are rigorously reviewed, monitored and continuously updated by our expert board to maintain accuracy, relevance, and timeliness.
-
Current Version
-
Mar 20, 2023Quiz Edited by
ProProfs Editorial Team -
Mar 27, 2012Quiz Created by
Golf_pro90
- Binary Code Quizzes
- Computer Concept Quizzes
- Computer Essential Quizzes
- Computer Forensics Quizzes
- Computer Hardware Quizzes
- Computer Networking Quizzes
- Computer Parts Quizzes
- Computer Programming Quizzes
- Computer Science Quizzes
- Computer Security Quizzes
- Computer Shortcut Key Quizzes
- Computer Skills Quizzes
- Computer Virus Quizzes
- Cyber Security Quizzes
- Data Quizzes
- Data Security Quizzes
- Hacking Quizzes
- HCI Quizzes
- Internet Quizzes
- IT SecurITy Quizzes
- Malware Quizzes
- Microprocessor Quizzes
- Network Quizzes
- Operating System Quizzes
- Phishing Quizzes
- Programming Language Quizzes
- Server Quizzes
- Software Quizzes
Back to top