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If the nested query result is independent of the current tuple being examined in the outer query, the nested query is called _______________.
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Uncorrelated
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TRUE OR FALSE? Domain constraints stipulate that it isn't a must for the actual values of an attribute in any tuple, to belong to a declared domain.
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False
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TRUE OR FALSE? Relationship types can't have attributes.
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False
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In redo logging, the incomplete transaction is ignored and the work of committed transactions are _______.
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repeated
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TRUE OR FALSE? When grouping data in SQL, some of the grouping attributes don’t have to appear in the ‘select’ clause.
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Fals
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TRUE OR FALSE? When locks are used in a transaction, there is also a possibility of deadlocks.
True
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How many kinds of Outer Joins are there?
3
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While a database is running, the selectivity value can be kept and maintained in the Database ____.
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Catalog
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In query optimization, the main heuristic rule that is used is to apply _________ before other operations.
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Select and project
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File blocks are a sequence of _______, containing all the records of the file.
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Blocks
blocks
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Select four reasons the Database Management System approach is preferred to the File System Storage approach, to the management of a database?
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It separates data from Meta data
Provision of program-data independence
Easy query formulation
System development of a database requires less effort
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Which of the following are contained in a block address?
Block number
Cylinder number
Surface number
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TRUE OR FALSE? To create an entity relationship model, the specifications are gathered and used to construct a diagrammatic notation.
True
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TRUE OR FALSE: If two relations are different, it is best to combine information from both relations by using the union operator.
false
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____________ are used, in order to capture the associated information for an entity.
Attributes
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The Closed World Assumption assumes that the relation name used as a predicate will be __________, if you substitute the tuple that is present in the current relational instance for the predicate.
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True
true
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In the equi-join operation, ________ is the only comparison operator used in the join condition.
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equality
Equality
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A unary operator that can be used to keep only the required attributes of relation instance is called a ____________.
Project operator
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A ___________ is the collection of a related piece of data that represents or captures the information about a real-world enterprise or part of an enterprise.
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database
Database
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A basic SQL query syntax contains a _________ clause, From clause and Where condition.
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Select
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TRUE OR FALSE? Physical Data Independence is when a Database Management System is architected such that the physical level scheme can be modified without affecting the logical or view level scheme.
True
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TRUE OR FALSE? When performing deletion in a B+ tree, underflows can occur.
True
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TRUE OR FALSE? Relation scheme R is in third normal form, If it is in second normal form, and in addition, a non-prime attribute of R is transitively dependent on any key of R.
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False
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Which of the following Normal Forms are defined in terms of functional dependencies?
Boyce-Codd Normal Form (BCNF)
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TRUE OR FALSE? In a database system, after system failure occurs, the recovery manager takes control.
True
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There is an algorithm that checks for whether a decomposition is indeed lossless or not. This algorithm works on a small m by n matrix, where m is the number of components that are there in the decomposition and n is the __________________.
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Total number of attributes that are present in the original scheme
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Which of the following types of attributes have atomic or indivisible values?
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Simple attributes
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If E1 and E2 are two entities that are connected to relationships R, which of the following possibilities indicates that an entity E1 may be associated with at most one entity E2 and that an E2 entity may be associated with at most one E1 entity?
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One to one
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ACID properties are important properties that should be satisfied by transaction processing systems. What does the acronym ACID stand for?
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Atomicity, Consistency, Isolation, Durability
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Which of the following conditions can cause the conflicting of a pair of operations in a schedule? Choose three answers:
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One of the operations is a write operation
Both operations deal with the same database item
The operations belong to two different transactions
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Set operations are applicable to two relations if their schemes are ___________
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Union-compatible
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Views give a specific user group a _____________ view of the database, without giving full access to the database.
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Restricted
restricted
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The query of a tuple relational calculus has _________ sides separated by a bar.
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2
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In terms of buffer usage for the nested loop join, how many blocks are reserved for storing the results of join?
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1
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