Immediate database modification technique uses
Both undo and redo.
Undo but no redo.
Redo but no undo.
Neither undo nor redo.
Correct Answer :
A. Both undo and redo.
Related Questions
An advantage of views is
Data security
Derived columns
Hiding of complex queries
All of the above
______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
Which of the following constitutes a basic set of operations for manipulating relational data?
Predicate calculus
Relational calculus
Relational algebra
SQL
In SQL the statement select * from R, S is equivalent to
Select * from R natural join S.
Select * from R cross join S.
Select * from R union join S.
Select * from R inner join S.
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.
The statement that is executed automatically by the system as a side effect of the modification of the database is
backup
assertion
recovery
trigger
A DBMS is a ____ user if at most one user can use the system and is mostly restricted to personal computer systems.
None
Multi
Single
Concurrent
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
Key to represent relationship between tables is called
primary key
secondary key
foreign key
none of the above
The full form of GUI is _________
Government Union Internet
Graphical Unit Interface
Graphical User Interface
Graphical University Interface
For correct behaviour during recovery, undo and redo operation must be
Commutative
Associative
idempotent
distributive
Whenever two independent one-to-many relationships are mixed in the same relation, a __________ arises.
Functional dependency
Multi-valued dependency
Transitive dependency
Partial dependency
The metadata is created by the
DML compiler
DML pre-processor
DDL interpreter
Query interpreter
Which of the following is not a characteristic of a relational database model?
Table
Tree like structure
Complex logical relationship
Records
The rule that a value of a foreign key must appear as a value of some specific table is called a
Referential constraint.
Index.
Integrity constraint.
Functional dependency.
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 .
The clause in SQL that specifies that the query result should be sorted in ascending or descending order based on the values of one or more columns is
View
Order by
Group by
Having
Grant and revoke are _____ statements.
TCL
DCL
DDL
DML
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
Precedence graphs help to find a
Serializable schedule.
Recoverable schedule.
Deadlock free schedule.
Cascadeless schedule.
The _____ category includes storage media that can be operated on directly by the computers central processing unit.
Primary storage
Secondary Storage
All
Tertiary Storage
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
Given the following relation S(SNO,SNAME,CITY) write a query to update the value of CITY to KANPUR for the supplier S1.
UPDATE S CITY = KANPUR WHERE SNO=S1
UPDATE S SET CITY = KANPUR FOR SNO=S1
UPDATE S SET CITY = KANPUR WHERE SNO=S1
UPDATE S RENAME CITY = KANPUR WHERE SNO=S1
Union operator is a :
Unary Operator
Ternary Operator
Binary Operator
Not an operator
Which of the following is a reason to model data?
Understand each user's perspective of data
Understand the data itself irrespective of the physical representation
Understand the use of data across application areas
All of the above
If an entity can belong to only one lower level entity then the constraint is
disjoint
partial
overlapping
single
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
Tr from next page
In an E-R diagram double lines indicate
Total participation.
Multiple participation.
Cardinality N.
None of the above.
The normalization was first proposed by .
Code
Codd
Boyce Codd
Boyce
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.