In multiple granularity of locks SIX lock is compatible with
IX
IS
S
SIX
Correct Answer :
B. IS
Related Questions
Key to represent relationship between tables is called
primary key
secondary key
foreign key
none of the above
Dependency preservation is not guaranteed in
BCNF
3NF
PJNF
DKNF
Which of the following is not a consequence of concurrent operations?
Lost update problem.
Update anomaly.
Unrepeatable read.
Dirty read.
A data type or format is specified for each _________
Relation
Tuple
Database
Domain
Which one is 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) C
(i) and (ii)
(iv) only
(i) and (iv)
(ii) and (iii)
What is a disjoint less constraint?
It requires that an entity belongs to no more than one level entity set.
The same entity may belong to more than one level.
The database must contain an unmatched foreign key value.
An entity can be joined with another entity in the same level entity set.
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
Manager salary details are hidden from the employee .This is
Conceptual level data hiding.
External level data hiding.
Physical level data hiding.
None of these.
The values of the attribute describes a particular
Entity set
File
Entity instance
Organization
Union operator is a :
Unary Operator
Ternary Operator
Binary Operator
Not an operator
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 .
The language that requires a user to specify the data to be retrieved without specifying exactly how to get it is
Procedural DML.
Non-Procedural DML.
Procedural DDL.
Non-Procedural DDL.
The drawback of shadow paging technique are
Commit overhead
Data fragmentation
Garbage collection
All of these
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
Consider 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
m+n and 0
m+n and |m-n|
mn and 0
mn and m+n
Relational Algebra does not have
Selection operator.
Projection operator.
Aggregation operators.
Division operator.
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
Precedence graphs help to find a
Serializable schedule.
Recoverable schedule.
Deadlock free schedule.
Cascadeless schedule.
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
operator is used to compare a value to a list of literals values that have been specified.
Like
COMPARE
BETWEEN
IN
The division operator divides a dividend A of degree m+n by a divisor relation B of degree n and produces a result of degree
m - 1
m + 1
m * m
m
An outstanding functionality of SQL is its support for automatic_____ to the target data.
programming
navigation
functioning
notification
Relational Algebra is
Data Definition Language .
Meta Language
Procedural query Language
None of the above
The collection of information stored in a database at a particular moment is called as ......
schema
instance of the database
data domain
independence
In a relational schema, each tuple is divided into fields called
Relations
Queries
Domains
All of the above
A weak entity has an ______ dependency on its owner entity, which can be used for both ON UPDATE and ON DELETE.
Direct
Indirect
Existence
No
If both the functional dependencies : X�Y and Y�X hold for two attributes X and Y then the relationship between X and Y is
M:N
M:1
1:M
It is an abstraction through which relationships are treated as higher level entities
Generalization.
Specialization.
Aggregation.
Inheritance.
Protection of data from unauthorized Disclosure results in loss of _______
Integrity
Availability
Confidentiality
Discretionary Security