Practice Library
All MCQs
Browse exam-wise, subject-wise, and country-wise MCQs with explanations.
Choose an option to check your answer.
A.
records are stored in a sorted sequence according to a search key
B.
records are randomly encrypted without order
C.
records are never updated after insertion
D.
records are stored as objects with methods
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Correct Answer: A. records are stored in a sorted sequence according to a search key
Explanation:
This statement is correct because sequential file organization means that records are stored in a sorted sequence according to a search key.
Choose an option to check your answer.
A.
a table without any rows
B.
an index that stores entries for some search key values, usually one per block
C.
a trigger that fires after commit
D.
an index entry for every record in the file
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Correct Answer: B. an index that stores entries for some search key values, usually one per block
Explanation:
The correct answer explains sparse index in the context of File Organization.
Choose an option to check your answer.
A.
a file organization remains unordered
B.
a database never allows backup
C.
a transaction moves the database from one valid state to another valid state
D.
a query always uses the same index
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Correct Answer: C. a transaction moves the database from one valid state to another valid state
Explanation:
consistency is used in Advanced DBMS because a transaction moves the database from one valid state to another valid state.
Choose an option to check your answer.
A.
all schedules with deadlocks are accepted
B.
transactions are serializable only when they use NoSQL
C.
queries are optimized by removing predicates
D.
a schedule can be transformed to a serial schedule by swapping non-conflicting operations
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Correct Answer: D. a schedule can be transformed to a serial schedule by swapping non-conflicting operations
Explanation:
This statement is correct because conflict serializability means that a schedule can be transformed to a serial schedule by swapping non-conflicting operations.
Choose an option to check your answer.
A.
all data is stored in the recovery log
B.
a hash function maps search key values to storage buckets
C.
transactions are executed on replicas only
D.
records are sorted using B-tree leaves only
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Correct Answer: B. a hash function maps search key values to storage buckets
Explanation:
The correct answer explains hash file organization in the context of File Organization.
Choose an option to check your answer.
A.
a trigger that fires after commit
B.
an index entry for every record in the file
C.
a table without any rows
D.
an index that stores entries for some search key values, usually one per block
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Correct Answer: D. an index that stores entries for some search key values, usually one per block
Explanation:
sparse index is used in Advanced DBMS because an index that stores entries for some search key values, usually one per block.
Choose an option to check your answer.
A.
a query always uses the same index
B.
a file organization remains unordered
C.
a transaction moves the database from one valid state to another valid state
D.
a database never allows backup
Show Answer
Correct Answer: C. a transaction moves the database from one valid state to another valid state
Explanation:
This statement is correct because consistency means that a transaction moves the database from one valid state to another valid state.
Choose an option to check your answer.
A.
a physical page size chosen by the OS
B.
a user-defined or structured type that can represent nested or composite values
C.
a password stored inside a table
D.
a data type that cannot be queried
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Correct Answer: B. a user-defined or structured type that can represent nested or composite values
Explanation:
The correct answer explains complex data type in object-relational databases in the context of Advance Data Models.
Choose an option to check your answer.
A.
removes the need for keys and constraints
B.
stores every record only as a plain text file
C.
executes queries without a DBMS
D.
it extends the relational model with complex types, inheritance, and methods while keeping tables
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Correct Answer: D. it extends the relational model with complex types, inheritance, and methods while keeping tables
Explanation:
The correct answer explains object-relational data model in the context of Advance Data Models.
Choose an option to check your answer.
A.
a data type that cannot be queried
B.
a physical page size chosen by the OS
C.
a password stored inside a table
D.
a user-defined or structured type that can represent nested or composite values
Show Answer
Correct Answer: D. a user-defined or structured type that can represent nested or composite values
Explanation:
complex data type in object-relational databases is used in Advanced DBMS because a user-defined or structured type that can represent nested or composite values.
Choose an option to check your answer.
A.
executes queries without a DBMS
B.
removes the need for keys and constraints
C.
it extends the relational model with complex types, inheritance, and methods while keeping tables
D.
stores every record only as a plain text file
Show Answer
Correct Answer: C. it extends the relational model with complex types, inheritance, and methods while keeping tables
Explanation:
object-relational data model is used in Advanced DBMS because it extends the relational model with complex types, inheritance, and methods while keeping tables.
Choose an option to check your answer.
A.
stores every record only as a plain text file
B.
executes queries without a DBMS
C.
removes the need for keys and constraints
D.
it extends the relational model with complex types, inheritance, and methods while keeping tables
Show Answer
Correct Answer: D. it extends the relational model with complex types, inheritance, and methods while keeping tables
Explanation:
This statement is correct because object-relational data model means that it extends the relational model with complex types, inheritance, and methods while keeping tables.
