Which of the following is not a consequence of concurrent operations?
Lost update problem.
Update anomaly.
Unrepeatable read.
Dirty read.
Correct Answer :
B. Update anomaly.
Related Questions
____specifies a search condition for a group or an aggregate.
GROUP BY Clause
HAVING Clause
FROM Clause
WHERE Clause
The clause alter table in SQL can be used to
add an attribute
delete an attribute
alter the default values of an attribute
all of the above
Union operator is a :
Unary Operator
Ternary Operator
Binary Operator
Not an operator
Key to represent relationship between tables is called
primary key
secondary key
foreign key
none of the above
Protection of data from unauthorized Disclosure results in loss of _______
Integrity
Availability
Confidentiality
Discretionary Security
operator is used to compare a value to a list of literals values that have been specified.
Like
COMPARE
BETWEEN
IN
A table can have only one
Secondary key
Alternate key
Unique key
Primary key
____ table store information about database or about the system.
SQL
System
Nested
None of these
If two relations R and S are joined, then the non matching tuples of both R and S are ignored in
left outer join
right outer join
full outer join
inner join
The transactions like adding an employee, enrolling a student in a course are examples of _______
Logical
Physical
None
Theoretical
A _____ is a logical unit of database processing that includes one or more data access operations that can include insertion, deletion, modification or retrieval operations.
Database
Data
Transaction
Record
………………… 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 _______ is a set of programs to use and / or modify this data.
DBMS
System
Program
Software
Wait-for graph is used for
detecting view serializability.
detecting conflict serializability.
deadlock prevention
deadlock detection
Grant and revoke are _____ statements.
TCL
DCL
DDL
DML
SQL server stores index information in the _____system table
system indexes
syst indexes
sys indexes
sysind
HSAM stands for ……….
Hierarchic Standard Access Method
Hierarchic Sequential Access Method
Hierarchic Sequential and Method
Hierarchic Standard and Method
A top-to-bottom relationship among the items in a database is established by a
Hierarchical schema
Network schema
Relational Schema
All of the above
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
The fact that all employees of a particular organization should not have salaries more than $10000 is a _____ constraint.
Schema
Tuple
Domain
Relational
DBMS helps achieve
Centralized control of data
Data independence
Both A and B
Neither A nor B
The normalization was first proposed by .
Code
Codd
Boyce Codd
Boyce
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
If an entity can belong to only one lower level entity then the constraint is
disjoint
partial
overlapping
single
A transaction is in state after the final statement has been executed.
partially committed
active
committed
none of the above
Which of the following is not a consequence of concurrent operations?
Lost update problem.
Update anomaly.
Unrepeatable read.
Dirty read.
The graphical representation of a query is .
B-Tree
graph
Query Tree
directed graph
In a multi-user database, if two users wish to update the same record at the same time, they are prevented from doing so by
jamming
password
documentation
record lock
______is a preferred method for enforcing data integrity
Constraints
Triggers
Stored procedure
Cursors
What are the desirable properties of a decomposition
Partition constraint.
Dependency preservation.
Redundancy.
Security.