Which of the following is not a characteristic of a relational database model?
Table
Tree like structure
Complex logical relationship
Records
Correct Answer :
B. Tree like structure
Related Questions
Between DRAM and magnetic disk storage another form of memory, called ______ memory is becoming common because it is non volatile.
RAM
Flash
Hard Disk
Secondary
The normal form that is not necessarily dependency preserving is
2NF
3NF
BCNF
4NF
For correct behaviour during recovery, undo and redo operation must be
Commutative
Associative
idempotent
distributive
Which of the following is not a consequence of concurrent operations?
Lost update problem.
Update anomaly.
Unrepeatable read.
Dirty read.
Relations produced from an E-R model will always be
First normal form.
Second normal form.
Third normal form.
Fourth normal form.
An advantage of the database management approach is
data redundancy increases
data is dependent on programs
data is integrated and can be accessed by multiple programs
none of the above
Which of the following is not a characteristic of a relational database model?
Table
Tree like structure
Complex logical relationship
Records
Maximum height of a B+ tree of order m with n key values is
Logm(n)
(m+n)/2
Logm/2(m+n)
None of these
What will be the number of columns and rows respectively obtained for the operation, A- B, 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
4,0
0,0
4,5
8,5
Which of the following addressing modes permits relocation without any change over in the code?
Indirect addressing
Indexed addressing
PC relative addressing
Base register addressing
In an ER model,_____ is described in the database by storing its data.
Entity
Attribute
Relationship
Notation
The cost of reading and writing temporary files while evaluating a query can be reduced by
building indices
pipelining
join ordering
none of the above
Relational Algebra is
Data Definition Language .
Meta Language
Procedural query Language
None of the above
The ______ language consists of SQL statements for operating on the data (insert, Modify, Delete) in tables that already exist.
Data Manipulation
Data Definition
Data Control
None
Which two files are used during operation of the DBMS?
Query languages and utilities
DML and query language
Data dictionary and transaction log
Data dictionary and query language
______ keyword is used to find the number of values in a column.
TOTAL
ADD
COUNT
SUM
As per equivalence rules for query transformation, selection operation distributes over
Union.
Set difference.
Intersection.
All of the above.
____specifies a search condition for a group or an aggregate.
GROUP BY Clause
HAVING Clause
FROM Clause
WHERE Clause
The keyword to eliminate duplicate rows from the query result in SQL is
DISTINCT
NO DUPLICATE
UNIQUE
None of the above
Cascading rollback is avoided in all protocol except
strict two-phase locking protocol.
tree locking protocol
two-phase locking protocol
validation based protocol.
Tree structures are used to store data in
Network model.
Relational model.
Hierarchical model.
File based system.
The data models defined by ANSI/SPARC architecture are
Conceptual, physical and internal
Conceptual, view and external
Logical, physical and internal
Logical, physical and view
In E-R Diagram total participation is represented by
Double lines
Single line
Dashed lines
Triangle
operator is used to compare a value to a list of literals values that have been specified.
Like
COMPARE
BETWEEN
IN
Wait-for graph is used for
detecting view serializability.
detecting conflict serializability.
deadlock prevention
deadlock detection
Data items grouped together for storage purposes are called a
record
string
title
list
………………… approach reduces time and effort required for design and lesser risk in database management.
Single global database
Multiple databases
Top-down approach
None of the above
The rule that a value of a foreign key must appear as a value of some specific table is called a
Referential constraint.
Index.
Integrity constraint.
Functional dependency.
When an E-R diagram is mapped to tables, the representation is redundant for
weak entity sets
weak relationship sets
strong entity sets
strong relationship sets
Which of the following concurrency control schemes is not based on the serializability property?
Two - phase locking
Graph-based locking
Time-stamp based locking
None of these .