What is the result of the following SQL statement ?
SELECT A.emp_Name, B.ph_num
FROM emp A LEFT OUTER JOIN phone B
ON A. emp_ID = B.emp_ID
A list of employees phone number
A list of all employees that have spouses, with phone number included in the list
A list of all employees names, including the phone number if they have one
Two lists : One list of employees, the other of phone numbers
Correct Answer :
C. A list of all employees names, including the phone number if they have one
Related Questions
Every Boyce-Codd normal form is in
3NF
2NF
1NF
none of the above
A table that displays data redundancies yields ____________ anomalies
Insertion
Deletion
Update
All of the above
Specialization is a
top-down approach.
bottom-up approach.
left-right approach.
none of the above
The raw facts and figures are:
Data
Data field
DBMS
DBASE
A subschema expresses
the logical view.
the physical view.
the external view.
all of the above.
Three SQL, DDL, CREATE commands are
Schema, Base and Table
Schema, Table and View
Base, Table and Schema
Key, Base and Table
In an E-R diagram attributes are represented by
rectangle.
square.
ellipse.
triangle.
Transaction processing is associated with everything below except
producing detail, summary, or exception reports.
recording a business activity.
confirming an action or triggering a response.
maintaining data.
Which of the following concurrency control schemes is not based on serializability property?
Two-phase locking
Timestamped based locking
Graph-based locking
none of the above
Which of the following layer uses trailer of the frame for error detection?
Transport layer
Network layer
Datalink layer
None of these
Benefit of database normalization is
smaller number of tables
higher query processing efficiency
reduced I/O for most queries
reduced data redundancy
Which of the following works as a filter?
UPDATE
DROP
ALTER
SELECT
In an object oriented model, one object can access data of another object by passing?
Instance variable
Variable
Message
Function
Transaction access data using two operations
read(), print()
read(), write()
scan(), write()
none of the above
A functional dependency between two or more non-key attributes is called
Transitive dependency
Partial transitive dependency
Functional dependency
Partial functional dependency
File organization that provides fast access to any arbitrary record
Hashed file
B-tree
Ordered file
Unordered file
The class based addressing is known as
Classless addressing
Classful addressing
Classified addressing
Classical addressing
Only one communication channel is needed rather than n channels to transmit data between two communicating devices
parallel
serial
analog
digital
Which of the following is true statement ?
SQL permits attribute names to be repeated in the same relation.
a SQL query automatically eliminates duplicates.
a SQL query will not work if there are no indexes on the relations
None of these
Query processing is
converting data to insert in a database
translation of query to lower form
range of activities involved in extracting data from a database
none of the above
Technique(s) used for data recovery after any failure
Logging
Recovery manager
Both A and B are true
Both A and B are false
Which of the following will NOT eliminates the ambiguities of a null value?
Define the attribute as required
Define subtypes
Define each attribute as having an initial value that is recognized as blank
Define supertypes
The transaction consists of all statements executed between
the begin transaction and end transaction
the start transaction and end transaction
the begin transaction and finish transaction
none of the above.
Repeaters operate in
i) Physical layer
ii) Datalink layer
iii) Transport layer
iv) Network layer
i and ii only
ii and iii only
ii only
i only
.................. is the loss of energy as the signal propagates outward, where the amount of energy depends on the frequency.
Noise
Delay distortion
Attenuation distortion
Dispersion
The degree of the table with 500 rows and 7 columns is
500
7
3500
none of these
A transaction which completes successfully is called
Granted
Committed
Compensated
Accomplished
In ………… paging we make copy of the current page table.
physical
logical
shadow
duplicate
The command used to delete a particular column in a relation
UPDATE
DROP
ALTER
DELETE
In defining the notion of the tuple variable, which one of the clause is useful?
as
by
from
none of the above