OBJECTIVE TYPE QUESTIONS
Choose the correct or the best alternative in the following:
Q.1Which of the following relational algebra operations do not require the participating
tables to be union-compatible?(A) Union (B) Intersection(C) Difference (D) JoinAns: (D)
Q.2Which of the following is not a property of transactions?(A) Atomicity (B) Concurrency(C) Isolation (D) DurabilityAns: (B)
Q.3Relational Algebra does not have(A) Selection operator. (B) Projection operator.(C) Aggregation operators. (D) Division operator.Ans: (C )
Q.4Checkpoints are a part of(A) Recovery measures. (B) Security measures.(C ) Concurrency measures. (D) Authorization measures.Ans: (A)
Q.5Tree structures are used to store data in(A) Network model. (B) Relational model.(C) Hierarchical model. (D) File-based system.Ans: (C )
Q.6The language that requires a user to specify the data to be retrieved without specifying
exactly how to get it is(A) Procedural DML. (B) Non-Procedural DML.(C) Procedural DDL. (D) Non-Procedural DDL.Ans: (B)
Q.7Precedence graphs help to find a
(A) Serializable schedule. (B) Recoverable schedule.(C) Deadlock-free schedule. (D) Cascade loss schedule.Ans: (A)
Q.8The rule that a value of a foreign key must appear as a value of some specific table is
called a(A) Referential constraint. (B) Index.(C) Integrity constraint. (D) Functional dependency.Ans: (A) The rule that a value of a foreign key must appear as a value of some specific
table is called a referential constraint. (Referential integrity constraint is concerned with
foreign key)Q.9 The clause in SQL that specifies that the query result should be sorted in ascending or
descending order based on the values of one or more columns is(A) View (B) Order by(C) Group by (D) HavingAns: (B) The clause in SQL that specifies that the query result should be sorted in
ascending or descending order based on the values of one or more columns is ORDER
BY. (ORDER BY clause is used to arrange the result of the SELECT statement)Q.10 What is a disjoint less constraint?(A) It requires that an entity belongs to no more than one level entity set.(B) The same entity may belong to more than one level.(C) The database must contain an unmatched foreign key value.(D) An entity can be joined with another entity in the same level entity set.Ans: (A) Disjoint less constraint requires that an entity belongs to no more than one level
entity set. (Disjoint less constraint means that an entity can be a member of at most one of
the subclasses of the specialization.)Q.11 According to the levels of abstraction, the schema at the intermediate level is called(A) Logical schema. (B) Physical schema.(C) Subschema. (D) Super schema.Ans: According to the levels of abstraction, the schema at the intermediate level is calledconceptual schema.
(Note: All the options given in the question are wrong.)Q.12 It is an abstraction through which relationships are treated as higher level entities(A) Generalization. (B) Specialization.(C) Aggregation. (D) Inheritance.Ans: (C ) It is an abstraction through which relationships are treated as higher level
entities Aggregation. (In ER diagram, aggregation is used to represent a relationship as an
entity set.)
Q.13 A relation is in ____________ if an attribute of a composite key is dependent on an
attribute of another composite key.(A) 2NF (B) 3NF(C) BCNF (D) 1NFAns: (B) A relation is in 3 NF if an attribute of a composite key is dependent on an
attribute of another composite key. (If an attribute of a composite key is dependent on an
attribute of another composite key then the relation is not in BCNF, hence it has to be
decomposed.)Q.14 What is data integrity?(A) It is the data contained in a database that is nonredundant.(B) It is the data contained in a database that is accurate and consistent.(C) It is the data contained in a database that is secured.(D) It is the data contained in a database that is shared.Ans: (B) (Data integrity means that the data must be valid according to the given
constraints. Therefore, the data is accurate and consistent.)Q.15 What are the desirable properties of a decomposition(A) Partition constraint. (B) Dependency preservation.(C) Redundancy. (D) Security.Ans: (B) What are the desirable properties of a decomposition – dependency preserving.
(Lossless join and dependency preserving are the two goals of the decomposition.)Q.16 In an E-R diagram double lines indicate(A) Total participation. (B) Multiple participation.(C) Cardinality N. (D) None of the above.Ans: (A)
Q.17The operation which is not considered a basic operation of relational algebra is(A) Join. (B) Selection.(C) Union. (D) Cross product.Ans: (A)
Q.18Fifth Normal form is concerned with(A) Functional dependency. (B) Multivalued dependency.(C) Join dependency. (D) Domain-key.Ans: (C)
Q.19Block-interleaved distributed parity is RAID level(A) 2. (B) 3(C) 4. (D) 5.Ans: (D)
Q.20 Immediate database modification technique uses(A) Both undo and redo. (B) Undo but no redo.(C) Redo but no undo. (D) Neither undo nor redo.Ans: (A)
Q.21In SQL the statement select * from R, S is equivalent to(A) Select * from R natural join S. (B) Select * from R cross join S.(C) Select * from R union join S. (D) Select * from R inner join S.Ans: (B)
Q.22Which of the following is not a consequence of concurrent operations?(A) Lost update problem. (B) Update anomaly.(C) Unrepeatable read. (D) Dirty read.Ans: (B)
Q.23As per equivalence rules for query transformation, selection operation distributes over(A) Union. (B) Intersection.(C) Set difference. (D) All of the above.Ans: (D)
Q.24 The metadata is created by the(A) DML compiler (B) DML pre-processor(C) DDL interpreter (D) Query interpreterAns: (C)
Q.25When an E-R diagram is mapped to tables, the representation is redundant for(A) weak entity sets (B) weak relationship sets(C) strong entity sets (D) strong relationship setsAns: (B)
Q.26When R , then the cost of computing ∩ S = φ R > < S is(A) the same as R × S (B) greater the R × S(C) less than R × S (D) cannot say anythingAns: (A)
Q.27In SQL the word ‘natural’ can be used with(A) inner join (B) full outer join(C) right outer join (D) all of the aboveAns: (A)
Q.28 The default level of consistency in SQL is(A) repeatable read (B) read committed(C) read uncommitted (D) serializable
Ans:(D)
Q.29If a transaction T has obtained an exclusive lock on item Q, then T can(A) read Q (B) write Q(C) both read and write Q (D) write Q but not read QAns: (C)
Q.30Shadow paging has(A) no redo (B) no undo(C) redo but no undo (D) neither redo nor undoAns: (A)
Q.31If the closure of an attribute set is the entire relation then the attribute set is a(A) superkey (B) candidate key(C) primary key (D) not a keyAns: (A)
Q.32DROP is a ______________ statement in SQL.(A) Query (B) Embedded SQL(C) DDL (D) DCLAns: (C)
Q.33If two relations R and S are joined, then the nonmatching tuples of both R and S are
ignored in(A) left outer join (B) right outer join(C) full outer join (D) inner joinAns: (D)
Q.34The keyword to eliminate duplicate rows from the query result in SQL is(A) DISTINCT (B) NO DUPLICATE(C) UNIQUE (D) None of the above` Ans: (C)
Q.35In 2NF(A) No functional dependencies (FDs) exist.(B) No multivalued dependencies (MVDs) exist.(C) No partial FDs exist.(D) No partial MVDs exist.
Ans: (C)
Q.36Which one is a correct statement?
Logical data independence provides following without changing application programs:(i) Changes in access methods.(ii) Adding new entities in database(iii) Splitting an existing record into two or more records(iv) Changing storage medium(A) (i) and (ii) (B) (iv) only, (C) (i) and (iv) (D) (ii) and (iii)Ans: (D)
Q.37In an E-R, Y is the dominant entity and X is a subordinate entity. Then which of the
following is incorrect:(A) Operationally, if Y is deleted, so is X(B) existence is dependent on Y.(C) Operationally, if X is deleted, so is Y.(D) Operationally, if X is deleted, & remains the same.Ans: (C)
Q.38Relational Algebra is(A) Data Definition Language .(B) Meta Language(C) Procedural query Language(D) None of the aboveAns: (C)
Q.39Which of the following aggregate functions does not ignore nulls in its results?.(A) COUNT . (B) COUNT (*)(C) MAX (D) MINAns: (B)
Q.40R (A,B,C,D) is a relation. Which of the following does not have a lossless join
dependency preserving BCNF decomposition(A) A B, B CD (B) A B, B C, C D .(C) AB C, C AD (D) A BCDAns: (D)
Q.41Consider the join of relation R with a relation S. If R has m tuples and S has n
tuples, then the maximum and minimum size of the join respectively are(A) m+n and 0 (B) m+n and |m-n|(C) mn and 0 (D) mn and m+nAns: (C)
Q.42 Maximum height of a B+ tree of order m with n key values is(A) Log(n) (B) (m+n)/2(C) Logm/2(m+n) (D) None of theseAns: (D)
Q.43Which one is true statement :(A) With finer degree of granularity of locking a high degree of concurrency is
possible.(B) Locking prevents non – serializable schedules.(C) Locking cannot take place at field level.(D) An exclusive lock on data item X is granted even if a shared lock is already
held on X.Ans: (A)
Q.44Which of the following statement on the view concept in SQL is invalid?(A) All views are not updateable(B) The views may be referenced in an SQL statement whenever tables are
referenced.(C) The views are instantiated at the time they are referenced and not when they
are defined.(D) The definition of a view should not have GROUP BY clause in it.Ans: (D)
Q.45Which of the following concurrency control schemes is not based on the
serializability property?(A) Two – phase locking (B) Graph-based locking(C) Time-stamp based locking (D) None of these.Ans: (D)
Q.46Which of the following is a reason to model data?(A) Understand each user’s perspective of data(B) Understand the data itself irrespective of the physical representation(C) Understand the use of data across application areas(D) All of the aboveAns: (D)
Q.47If an entity can belong to only one lower level entity then the constraint is(A) disjoint (B) partial(C) overlapping (D) singleAns: (B)
Q.48The common column is eliminated in(A) theta join (B) outer join
(C) natural join (D) composed joinAns: (C )
Q.49In SQL, testing whether a subquery is empty is done using(A) DISTINCT (B) UNIQUE(C) NULL (D) EXISTSAns: (D)
Q.50Use of UNIQUE while defining an attribute of a table in SQL means that the attribute
values are(A) distinct values (B) cannot have NULL(C) both (A) & (B) (D) same as primary keyAns: (C)
Q.51The cost of reading and writing temporary files while evaluating a query can be reduced
by(A) building indices (B) pipelining(C) join ordering (D) none of the aboveAns: (B)
Q.52A transaction is in __________ state after the final statement has been executed.(A) partially committed (B) active(C) committed (D) none of the aboveAns: (C)
Q.53In multiple granularities of locks SIX lock is compatible with(A) IX (B) IS(C) S (D) SIXAns: (B)
Q.54The statement that is executed automatically by the system as a side effect of the
modification of the database is(A) backup (B) assertion(C) recovery (D) triggerAns: (D)
Q.55The normal form that is not necessarily dependency preserving is(A) 2NF (B) 3NF(C) BCNF (D) 4NFAns: (A)
Q.56A functional dependency of the form x → y is trivial if
(A) y ⊆ x (B) y ⊂ x(C) x ⊆ y (D) x ⊂ yAns: (A)
Q.57The normalization was first proposed by ______________.(A) Code (B) Codd(C) Boyce Codd (D) BoyceAns: (B)
Q.58The division operator divides a dividend A of degree m+n by a divisor relation B of
degree n and produces a result of degree(A) m – 1 (B) m + 1(C) m * m (D) mAns: (D)
Q.59Which of the following is not a characteristic of a relational database model?(A) Table (B) Tree like structure(C) Complex logical relationship (D) RecordsAns: (B)
Q.60Assume transaction A holds a shared lock R. If transaction B also requests for a shared
lock on R.(A) It will result in a deadlock situation.(B) It will immediately be rejected.(C) It will immediately be granted.(D) It will be granted as soon as it is released by A .Ans: (C)
Q.61In E-R Diagram total participation is represented by(A) double lines (B) Dashed lines(C) single line (D) TriangleAns: (A)
Q.62The FD A → B, DB → C implies(A) DA → C (B) A → C(C) B → A (D) DB → AAns: (A)
Q.63The graphical representation of a query is ________.(A) B-Tree (B) graph(C) Query Tree (D) directed graph
Ans: (C)
Q.64Union operator is a:(A) Unary Operator (B) Ternary Operator(C) Binary Operator (D) Not an operatorAns: (C)
Q.65Relations produced from an E-R model will always be(A) First normal form. (B) Second normal form.(C) Third normal form. (D) Fourth normal form.Ans: (A)
Q.66Manager salary details are hidden from the employee.This is(A) Conceptual level data hiding.(B) External level data hiding.(C) Physical level data hiding.(D) None of these.Ans: (A)
Q.67Which of the following is true for network structure?(A) It is a physical representation of the data.(B) It allows many to many relationships.(C) It is conceptually simple.(D) It will be the dominant database of the future.Ans: (A)
Q.68Which two files are used during operation of the DBMS?(A) Query languages and utilities(B) DML and query language(C) Data dictionary and transaction log(D) Data dictionary and query languageAns: (C )
Q.69A list consists of last names, first names, addresses and pin codes. If all people in the
list have the same last name and same pin code a useful key would be(A) the pin code(B) the last name(C) the compound key first name and last name(D) Tr from next pageAns: (C )
Q.70In b-tree the number of keys in each node is ____ than the number of its children.(A) one less (B) same(C) one more (D) half
Ans: (A)
Q.71The drawback of shadow paging technique are(A) Commit overhead (B) Data fragmentation(C) Garbage collection (D) All of theseAns: (D)
Q.72Which normal form is considered adequate for normal relational database design?(A) 2NF (B) 5NF(C) 4NF (D) 3NFAns: (D)
Q.73Which of the following addressing modes permits relocation without any change over
in the code?(A) Indirect addressing (B) Indexed addressing(C) PC relative addressing (D) Base register addressingAns: (B)
Q.74In a multi-user database, if two users wish to update the same record at the same time,
they are prevented from doing so by(A) jamming (B) password(C) documentation (D) record lockAns: (D)
Q.75The values of the attribute describes a particular_____________(A) Entity set (B) File(C) Entity instance (D) OrganizationAns: (C)
Q.76Which of the following relational algebraic operations is not from set theory?(A) Union (B) Intersection(C) Cartesian Product (D) SelectAns: (D)
Q.77Which of the following ensures the atomicity of the transaction?(A) Transaction management component of DBMS(B) Application Programmer(C) Concurrency control component of DBMS(D) Recovery management component of DBMSAns: (A)
Q.78If both the functional dependencies: X→Y and Y→X hold for two attributes X and Y
then the relationship between X and Y is
(A) M: N
(B) M:1(C) 1:1
(D) 1:MAns: (C)
Q.79What will be the number of columns and rows respectively obtained for the operation, AB, if A B are Base union compatible and all the rows of a are common to B? Assume A
has 4 columns and 10 rows, and B has 4 columns and 15 rows(A) 4,0 (B) 0,0(C) 4,5 (D) 8,5Ans: (A)
Q.80For correct behavior during recovery, undo and redo operation must be(A) Commutative (B) Associative(C) idempotent (D) distributiveAns: (C)
Q.81Which of the following is not a consequence of non-normalized database?(A) Update Anomaly (B) Insertion Anomaly(C) Redundancy (D) Lost update problemAns: (D)
Q.82Which of the following is true for relational calculus?(A) ∀x(P(x))≡¬(∃x)(¬P(x)) (B) ∀x(P(x))≡¬(∃x)(P(x))(C) ∀x(P(x))≡(∃x)(¬P(x)) (D) ∀x(P(x))≡(∃x)(P(x))Ans: (A)
Q.83The part of a database management system which ensures that the data remains in a
a consistent state is(A) authorization and integrity manager(B) buffer manager(C) transaction manager(D) file managerAns: (C)
Q.84Relationships among relationships can be represented in an-E-R model using(A) Aggregation (B) Association(C) Weak entity sets (D) Weak relationship setsAns: (A)
Q.85In tuple relational calculus P1 AND P2 is equivalent to(A) (¬P1OR¬P2). (B) ¬(P1OR¬P2).(C) ¬(¬P1OR P2). (D) ¬(¬P1OR ¬P2).
Ans: (D)
Q.86If α→β holds then so does(A) γα→γβ (B) α→→γβ(C) both (A) and (B) (D) None of the aboveAns: (A)
Q.87Cascading rollback is avoided in all protocol except(A) strict two-phase locking protocol.(B) tree locking protocol(C) two-phase locking protocol(D) validation based protocol.Ans: (D)
Q. 88Wait-for graph is used for(A) detecting view serializability. (B) detecting conflict serializability.(C) deadlock prevention (D) deadlock detectionAns: (D)
Q.89The expression σθ1(E1 θ2E2) is the same as(A) E1 θ1^ θ2E2 (B) σθ1 E1^σθ2 E2(C) E1 θ1∨ θ2E2 (D) None of the aboveAns: (A)
Q.90The clause alter table in SQL can be used to(A) add an attribute(B) delete an attribute(C) alter the default values of an attribute(D) all of the aboveAns: (D)
Q. 91The data models defined by ANSI/SPARC architecture are(A) Conceptual, physical and internal(B) Conceptual, view and external(C) Logical, physical and internal(D) Logical, physical and viewAns: (D)
Q.92Whenever two independent one-to-many relationships are mixed in the same relation, a
_______ arises.(A) Functional dependency (B) Multi-valued dependency(C) Transitive dependency (D) Partial dependency
AC14/AT11 Database Management Systems14Ans:(B)
Q.93A table can have only one(A) Secondary key (B) Alternate key(C) Unique key (D) Primary keyAns: (D)
Q.94Dependency preservation is not guaranteed in(A) BCNF (B) 3NF(C) PJNF (D) DKNFAns: (A)
Q.95Which is the best file organization when data is frequently added or deleted from a file?(A) Sequential (B) Direct(C) Index sequential (D) None of the aboveAns: (B)
Q.96Which of the following constitutes a basic set of operations for manipulating relational
data?(A) Predicate calculus (B) Relational calculus(C) Relational algebra (D) SQLAns: (C)
Q.97An advantage of views is(A) Data security (B) Derived columns(C) Hiding of complex queries (D) All of the aboveAns: (A)
Q.98Which of the following is not a recovery technique?(A) Deferred update (B) Immediate update(C) Two-phase commit (D) Shadow pagingAns: (C)
Q.99Isolation of the transactions is ensured by(A) Transaction management (B) Application programmer(C) Concurrency control (D) Recovery managementAns: (C)
Q.100_______ operator is used to compare a value to a list of literals values that have been
specified.(A) Like (B) COMPARE(C) BETWEEN (D) INAns: (A)
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