The collection of information stored in a database at a particular moment is called as ......
schema
instance of the database
data domain
independence
Correct Answer :
B. instance of the database
Related Questions
operator is used to compare a value to a list of literals values that have been specified.
Like
COMPARE
BETWEEN
IN
______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
In a relational schema, each tuple is divided into fields called
Relations
Queries
Domains
All of the above
Data items grouped together for storage purposes are called a
record
string
title
list
DROP is a statement in SQL.
Query
Embedded SQL
DDL
DCL
An outstanding functionality of SQL is its support for automatic_____ to the target data.
programming
navigation
functioning
notification
The collection of information stored in a database at a particular moment is called as ......
schema
instance of the database
data domain
independence
In an ER model,_____ is described in the database by storing its data.
Entity
Attribute
Relationship
Notation
Tree structures are used to store data in
Network model.
Relational model.
Hierarchical model.
File based system.
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
A list consists of last names, first names, addresses and pin codes. If all people in the list have the same last name and same pin code a useful key would be
the pin code
the last name
the compound key first name and last name
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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.
The values of the attribute describes a particular
Entity set
File
Entity instance
Organization
The graphical representation of a query is .
B-Tree
graph
Query Tree
directed graph
Which of the following constitutes a basic set of operations for manipulating relational data?
Predicate calculus
Relational calculus
Relational algebra
SQL
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
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
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.
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 .
Which of the following relational algebraic operations is not from set theory?
Union
Intersection
Cartesian Product
Select
The ____ operator joins two or more conditions and displays rows only if that rows data satisfies all conditions specified.
OR
AND
NOT
ALL
____specifies a search condition for a group or an aggregate.
GROUP BY Clause
HAVING Clause
FROM Clause
WHERE Clause
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 _____ category includes storage media that can be operated on directly by the computers central processing unit.
Primary storage
Secondary Storage
All
Tertiary Storage
_____ command can be used to modify a column in a table
alter
update
set
create
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.
____ table store information about database or about the system.
SQL
System
Nested
None of these
The common column is eliminated in
theta join
outer join
natural join
composed join
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