Download CUSTOMER_CODE SMUDE DIVISION_CODE SMUDE

CUSTOMER_CODE
SMUDE
DIVISION_CODE
SMUDE
EVENT_CODE
APR2016
ASSESSMENT_CODE BC0050_APR2016
QUESTION_TYPE DESCRIPTIVE_QUESTION
QUESTION_ID
4175
QUESTION_TEXT Explain the different modes of shutting down process in database.
SCHEME OF
EVALUATION
The syntax of the SHUT DOWN command is
SHUT DOWN [NORMAL|IMMEDIATE|TRANSACTIONAL|ABORT]
NORMAL: This is default mode for shutting down the database. The
oracle server waits for all currently connected users to disconnected users
to disconnect their sessions. No new connections are permitted. A
checkpoint is performed on the entire database and the files are closed.
When a database is shutdown in this mode an instance recovery will not
need to be done during the subsequent startup. (2.5 marks)
IMMEDIATE: when a database is shutdown in this mode. The oracle
server automatically rolls back all currently active transactions. After the
transactions have been rolled back the user sessions are terminated. No
new connections are allowed. The database is then closed, dismounted
and the instance released. No instance recovery will be performed during
subsequent startup. (2.5 marks)
TRANSACTIONAL: when the database is shutdown using this option, all
currently active transactions completes the user is automatically
dismounted. No new user connections will be allowed. The database is
then closed dismounted and the instance released. No instance recovery
will be performed during subsequent startup. (2.5 marks)
ABORT: When the database is shutdown using this option, the instance
is shutdown. This is a case of an improper shutdown. No check pointing
is done. All user connections are abnormally terminated. The database is
not closed or dismounted. (2.5 marks) Total 10 marks
QUESTION_TYPE
DESCRIPTIVE_QUESTION
QUESTION_ID
4179
QUESTION_TEXT
Explain any FIVE features of Heterogeneous Services agent
1.Distributed transactions
2.Transparent SQL access
SCHEME OF EVALUATION 3.Procedural access
4.Data dictionary translations
5.Pass-through SQL
6.Accessing stored procedures
7.National language support
8.Multi-threaded agents
9.Agent self-registration
10.Management interface
(Any FIVE from the above which carries 2 marks each)
QUESTION_TYPE
DESCRIPTIVE_QUESTION
QUESTION_ID
72868
QUESTION_TEXT
Explain any 4 physical files of the database.
SCHEME OF EVALUATION
Datafiles
Control files
Parameter file
Archive file
(Each with Explanation 2.5*4)
QUESTION_TYPE
DESCRIPTIVE_QUESTION
QUESTION_ID
113960
Give the description of the following 5 characteristics of query
processors:
QUESTION_TEXT
a.
Languages
b.
Types of optimization
c.
Optimization timing
d.
e.
a.
b.
SCHEME OF
EVALUATION
Statistics
Decision sites
Languages: The input language to the query processor can be
based on relational calculus or relational algebra. In distributed
context, the output language is generally some form of relational
algebra augmented with communication primitives.
Types of Optimization: Conceptually, query optimization is to
choose a best point of solution space that leads to the minimum cost.
A popular approach called exhaustive search is used. This is a
method where heuristic techniques are used. In both centralized and
distributed systems a common heuristic is to minimize the size of
intermediate relations. Performing unary operations first and
ordering the binary operations by the increasing size of their
intermediate relations can do this.
c.
d.
e.
Optimization Timing: A query may be optimized at different
times relative to the actual time of query execution. Optimization
can be done statically before executing the query or dynamically as
the query is executed. The main advantage of the later method is that
the actual sizes of the intermediate relations are available to the
query processor, thereby minimizing the probability of a bad choice.
Statistics: The effectiveness of the query optimization is based on
statistics on the database. Dynamic query optimization requires
statistics in order to choose the operation that has to be done first.
Static query optimization requires statistics to estimate the size of
intermediate relations. The accuracy of the statistics can be
improved by periodical updating.
Decision Sites: Most of the systems use centralized decision
approach, in which a single site generates the strategy. However, the
decision process could be distributed among various sites
participating in the elaboration of the best strategy. The centralized
approach is simpler but requires the knowledge of the complete
distributed database where as the distributed approach requires only
local information.
(2 marks each)
QUESTION_TYPE
DESCRIPTIVE_QUESTION
QUESTION_ID
113966
Briefly explain the properties of Transaction application
QUESTION_TEXT
a.
i.
ii.
SCHEME OF EVALUATION b.
c.
d.
Atomicity
(2 marks)
Transaction aborts
System crashes (1 mark each)
Durability
(2 marks)
Serializability
(2 marks)
Isolation
(2 marks)
QUESTION_TYPE
DESCRIPTIVE_QUESTION
QUESTION_ID
113967
QUESTION_TEXT
Explain the notions of Transparency and Site autonomy
Transparency:
(5 marks)
SCHEME OF EVALUATION a.
Location transparency
b.
Replication transparency
Site autonomy
(5 marks)