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Through what interface are parameters entered into an information system?
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Graphical User Interface
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TRUE OR FALSE? In the relational representation of strong entity sets, the primary key of the entity will also be the primary key of the relational table.
True
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TRUE OR FALSE? It is preferable to use operating system services for managing disc space.
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False
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In the hashed files method of file organisation, data files are organised in ______.
Buckets
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TRUE OR FALSE? If intermediate tables can be handled in the memory, depending on their size, they should be handled in the memory.
True
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A schedule is called cascadeless or ACR (Avoiding Cascaded Rollbacks) if in the schedule, transactions read only values written by ___________ transactions.
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committed
Committed
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In disk storage, the ease of carrying out an operation on a file depends on the organisation of the file and the availability of the ________.
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Indexes
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The Bottom-up approach for relational database design, is also called the _______ approach.
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Synthesis
synthesis
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Which of the following is not included in the update entry of undo-redo logging?
Transaction item
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A selector operator of relational algebra is represented by the ________ symbol.
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Sigma
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Which of the following conditions allows Views in a database to be updated?
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View includes the primary key of the base table
View is not defined using ‘group by’ clause and aggregate functions
The View is defined on a single base table
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The Linear hashing technique employed in hashing for dynamic file organisation, requires a separate directory structure.
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False
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Which of the following is a component of an SQL standard? Select four:
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Data Definition Language
Transaction control
Data Manipulation Language
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TRUE OR FALSE? A schedule is called conflict serializable, if it is conflict equivalent to some serial schedule.
True
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TRUE OR FALSE? In an implication symbol truth table, If P is true and Q is false, the implication will be true.
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False
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Which of the following is true about BCNF?
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BCNF is an acronym for Boyce-Codd normal form
The Boyce-Codd normal form further removes redundancy
Redundancy allowed by 3NF isn’t allowed by BCNF
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TRUE OR FALSE? When deleting an attribute in a defined schema, you need to specify what is to be done about the constraints or views that refer to the attribute being dropped.
True
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How many properties is the decomposition of a relational scheme required to satisfy?
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2
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TRUE OR FALSE? An unsafe tuple relational calculus is an expression whose results uses values that do not appear in the instances of any of the database relations.
True
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Tuple relational calculus is a ___________ query language.
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Declarative
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TRUE OR FALSE? Deleting only part of the tuple of a table in a database is possible?
True
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TRUE OR FALSE? Reflexive rule, augmentation rule, and transitive rules are called Armstrong’s Axioms.
True
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Student (rollNO, name, degree, year, sex, deptNo)
Department (deptId, name, hod, phone)
Course (CourseId, cname, credit, deptNo)
If a query is to obtain the name and roll number of male B.Eng. students, what relations would be needed?
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Student
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TRUE OR FALSE? Table aliases are required if an attribute name appears in more than one table, or when the same relation appears twice in the From clause.
True
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Join operation can be realised through cross-product operation followed by a __________ operation.
Selection
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In the B++ trees, the _____ node entries points to the data records.
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Leaf
leaf
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The reliability of the set of disks is modeled using the MTTF. What is the full meaning of MTTF?
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Mean Time to Failure
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A _________ is a subsystem of a Relational Database Management System, where the information about updates that are being done to the database, are recorded in a separate place.
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Log
log
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Which of the following is true about a Database Management System? Choose all that apply:
It is capable of managing several databases at a time
It is generic in nature
It is not tied to a single database
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Which of the following are methods of organising files in disk storage?
Hashed files
Heap files
Sorted files
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TRUE OR FALSE? Every functional dependency on a relational scheme is also a multivalued dependency.
True
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A _________ key is a group of attributes used to refer tuples from one relation, to tuples in another relation.
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Foreign
foreign
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The extendible hashing technique makes use of a directory that has a certain depth called ______ depth.
global
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