If an entity can belong to only one lower level entity then the constraint is
disjoint
partial
overlapping
single
Correct Answer :
B. partial
Related Questions
In an E-R, Y is the dominant entity and X is a subordinate entity. Then which of the following is incorrect :
Operationally, if Y is deleted, so is X
existence is dependent on Y.
Operationally, if X is deleted, so is Y.
Operationally, if X is deleted, & remains the same.
_____ database is used to provide statistical information or summaries of values based on various criteria.
Statistical
Mathematical
Normalized
Un normalized
The part of a database management system which ensures that the data remains in a consistent state is
authorization and integrity manager
buffer manager
transaction manager
file manager
The full form of GUI is _________
Government Union Internet
Graphical Unit Interface
Graphical User Interface
Graphical University Interface
Drop Table cannot be used to drop a table referenced by a ______ constraint.
Primary Key
Local Key
Foreign Key
Composite Key
The _______ is a set of programs to use and / or modify this data.
DBMS
System
Program
Software
What is data integrity?
It is the data contained in database that is non redundant.
It is the data contained in database that is accurate and consistent.
It is the data contained in database that is secured.
It is the data contained in database that is shared.
Cascading rollback is avoided in all protocol except
strict two-phase locking protocol.
tree locking protocol
two-phase locking protocol
validation based protocol.
_____ command can be used to modify a column in a table
alter
update
set
create
Which of the following is not a property of transactions?
Atomicity
Concurrency
Isolation
Durability
Union operator is a :
Unary Operator
Ternary Operator
Binary Operator
Not an operator
A table can have only one
Secondary key
Alternate key
Unique key
Primary key
The ______ indexes are forced to store only record IDs in the data structure and require at least one additional I/O Operation to retrieve the actual record.
Clustered
Hashed
Un-clustered
Collision
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
Create a table with the following attributes: Employee(EMPNO integer, EMPNAME of 10 characters)
Create table Employee(EMPNO int, EMPNAME char(10));
Create table Employee(EMPNO integer, EMPNAME String(10));
Create table Emplo(EMPNO number, EMPNAME string);
Create table Emp(EMPNO int, EMPNAME char(10));
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
A data type or format is specified for each _________
Relation
Tuple
Database
Domain
In an ER model,_____ is described in the database by storing its data.
Entity
Attribute
Relationship
Notation
Employees in a company are each assigned their own office, i.e. for each employee there exists a unique office and for each office there exists a unique employee; This statement is an example of ____ type of relation.
1:1
1: Many
Many: One
Many : Many
According to the levels of abstraction, the schema at the intermediate level is called
Logical schema.
Physical schema.
Subschema.
None of the above.
A transaction is in state after the final statement has been executed.
partially committed
active
committed
none of the above
Assume transaction A holds a shared lock R. If transaction B also requests for a shared lock on R.
It will result in a deadlock situation.
It will immediately be rejected.
It will immediately be granted.
It will be granted as soon as it is released by A .
Data items grouped together for storage purposes are called a
record
string
title
list
Which of the following constitutes a basic set of operations for manipulating relational data?
Predicate calculus
Relational calculus
Relational algebra
SQL
Data independence means
data is defined separately and not included in programs.
programs are not dependent on the physical attributes of data
programs are not dependent on the logical attributes of data
both B and C
Relational Algebra is
Data Definition Language .
Meta Language
Procedural query Language
None of the above
Precedence graphs help to find a
Serializable schedule.
Recoverable schedule.
Deadlock free schedule.
Cascadeless schedule.
______is a special type of integrity constraint that relates two relations & maintains consistency across the relations.
Domain Integrity Constraints
Referential Integrity Constraints
Domain Constraints
Entity Integrity Constraints
The relational model is based on the concept that data is organized and stored in two-dimensional tables called ______
Fields
Records
Relations
Keys
Isolation of the transactions is ensured by
Transaction management
Application programmer
Concurrency control
Recovery management