Which of the following statement on the view concept in SQL is invalid?
All views are not updateable
The views may be referenced in an SQL statement whenever tables are referenced.
The views are instantiated at the time they are referenced and not when they are defined.
The definition of a view should not have GROUP BY clause in it.
Correct Answer :
D. The definition of a view should not have GROUP BY clause in it.
Related Questions
The set of all values that can be taken by the attribute is called as _______ of the attribute.
Tuple
Cardinality
Degree
Domain
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));
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
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
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
The transactions like adding an employee, enrolling a student in a course are examples of _______
Logical
Physical
None
Theoretical
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)
The relational model is based on the concept that data is organized and stored in two-dimensional tables called ______
Fields
Records
Relations
Keys
______contains information that defines valid values that are stored in a column or data type.
Default
Index
Rule
View
SQL server stores index information in the _____system table
system indexes
syst indexes
sys indexes
sysind
Change Staff table by removing default of Assistant for position column
ALTER TABLE Staff ALTER position DROP DEFAULT;
ALTER TABLE Staff ALTER position DEFAULT;
ALTER TABLE Staff ALTER DROP DEFAULT;
MODIFY Staff ALTER position DROP DEFAULT;
HSAM stands for ……….
Hierarchic Standard Access Method
Hierarchic Sequential Access Method
Hierarchic Sequential and Method
Hierarchic Standard and Method
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.
The graphical representation of a query is .
B-Tree
graph
Query Tree
directed graph
Which of the following is not a consequence of non-normalized database?
Update Anomaly
Insertion Anomaly
Redundancy
Lost update problem
If an entity can belong to only one lower level entity then the constraint is
disjoint
partial
overlapping
single
Which of the following is not a property of transactions?
Atomicity
Concurrency
Isolation
Durability
The data in the database at a particular moment of time is called the _______
Snapshot
Dynaset
Stateless
Stateful
In SQL, testing whether a subquery is empty is done using
DISTINCT
UNIQUE
NULL
EXISTS
In b-tree the number of keys in each node is than the number of its children.
one less
same
one more
half
DBMS is a collection of _____ that enables user to create and maintain a database.
Keys
Program
Translators
Language Activity
Which of the following ensures the atomicity of the transaction?
Transaction management component of DBMS
Application Programmer
Concurrency control component of DBMS
Recovery management component of DBMS
The collection of information stored in a database at a particular moment is called as ......
schema
instance of the database
data domain
independence
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.
………………… 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 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
Drop Table cannot be used to drop a table referenced by a ______ constraint.
Primary Key
Local Key
Foreign Key
Composite Key
Dependency preservation is not guaranteed in
BCNF
3NF
PJNF
DKNF
operator is used to compare a value to a list of literals values that have been specified.
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