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Pearl eyes from my own collection. Use at your own risk.
Mirroring of disks increases reliability but uses _______% more disks.
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50
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Which option is not part of the Armstrong Inference rules?
Set rule
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TRUE OR FALSE? A recovery manager is what takes control of the database system, after it recovers from a crash.
True
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Consider a 1: N relationship:
Let S be the participating entity on the N side and T the other entity while S’ and T’ are the corresponding tables.
Which of the following is part of the approach to handling the 1: N relationship? Choose two answers:
Include the primary key of T’ as foreign key in S’
Include any simple attribute of 1: N relation type as attributes of S’
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In ____________ query language, query specification involves giving a step-by-step process of obtaining the query result.
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Procedural
procedural
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To reduce the input to the projection operand, the selection operation should be applied after the _______ operation.
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Project
project
Projection
Projection
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Which of the following is an entity set whose members owe their existence to some entity in a strong entity set?
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Weak entity
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The type of data model that describes the logical representation of data without giving details of physical representation, is called the _________________ data model.
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Representational
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The index entry of a clustering index, is a distinct value of the ordering field and address of the ______ block, that has a record with the ordering field value.
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First
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TRUE OR FALSE? In the completeness of Armstrong’s Axioms, if a set of attributes F entails attribute X and determines attribute Y, then this implies X determines Y can't be derived from F.
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False
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How many aggregate functions are provided in SQL?
5
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Match the correct index types and descriptions together:
Index built on non-ordering field of a file
Secondary index
Index built on ordering key field of a file
Primary index
Index built on ordering non-key field of a file
Clustering index
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In general, if an entity, even though not of independent existence, participates in other relationships on its own, it is captured as a ________ entity.
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weak
Weak
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Normal Forms are conditions that if satisfied by certain database design or schema, the database or schema will not have certain kinds of problem.
True
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In the API based approach of accessing database, there are certain steps to accessing data from a host language program.
Select the data source
Load the appropriate driver dynamically
Establish the connection
Authenticate the client
Work with database
Close the connection
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In SQL, UNION, INTERSECTION and EXCEPT, operators are used and can perform union, intersection and ______________ respectively.
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difference
Difference
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TRUE OR FALSE? Secondary indexes can’t be converted to multi-level indexes.
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False
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The high-level language in which a database application is developed is called the __________.
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Host language
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From the transaction processing system point of view, which of the following ACID properties is the most important?
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Atomicity and Isolation
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What special variable is used to determine if an SQL statement has executed successfully or not?
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SQLSTATE
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Lossless joins are also called ________ decomposition.
Non additive
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TRUE OR FALSE? Queries with universally quantified predicates, can only be specified after translating them to use existential quantifiers.
True
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The integrity constraints in SQL, are also called the _______ constraints.
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table
Table
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Which transaction isolation level guarantees that dirty reads, unrepeatable reads, and phantoms won’t arise?
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Serializable
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TRUE OR FALSE? A multi-valued attribute can be directly stored as a value in a cell of a relational table.
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False
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Why are there no duplicate tuples in a relational instance?
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Relational instance is defined as a set
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If a functional dependency X determines Y, where Y is a subset of X, it is called ___________ functional dependency.
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Trivial
trivial
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What transaction operation is issued when a transaction has successfully completed its sequence of operations?
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Commit
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____________ are used, in order to capture the associated information for an entity.
Attributes
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In using a cross-product operator to retrieve data from a relational scheme, why is it necessary to rename attributes?
To help formulate the query
To ensure that the cross product has distinct attribute names
To help understand the query
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A relation scheme R with respect to a set of functional dependencies, is said to
be in ________________, if every non-prime attribute is fully functionally dependent on any key of R.
Second normal form
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The choice of algorithm for a join operation depends on which of the following?
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Selectivity of the join condition !!!! ansver inkorr
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TURE OR FALSE? The same attribute name is not allowed to occur twice in a relational scheme.
True
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