Interested to Buy Any Domain ? << Click Here >> for more details...
Wat is isolation level and when do u use them?
- 1 Answers
- 20922 Views
- HP, IBM, I also Faced
- E-Mail Answers
Answer / ram
Specifies the transaction isolation levels that provide the
necessary
consistency and concurrency control between transactions in
the job and
other transactions for optimal performance.
Because Oracle does not
prevent other transactions from modifying the data read by
a query, that
data may be changed by other transactions between two
executions of the
query. Thus, a transaction that executes a given query
twice may
experience both nonrepeatable reads and phantoms. Use one
of the following
transaction isolation levels:
Read Committed. Takes exclusive locks on modified data and
sharable locks
on all other data. Each query executed by a transaction
sees only data
that was committed before the query (not the transaction)
began. Oracle
queries never read dirty, that is, uncommitted data. This
is the default.
Serializable. Takes exclusive locks on modified data and
sharable locks on
all other data. It sees only those changes committed when
the transaction
began plus those made by the transaction itself through
INSERT, UPDATE,
and DELETE statements. Serializable transactions do not
experience
nonrepeatable reads or phantoms.
Read-only. Sees only those changes that were committed when
the
transaction began. This level does not permit INSERT,
UPDATE, and DELETE
statements.
| Is This Answer Correct ? | 2 Yes | 3 No |
30 jobs are running in unix.i want to find out my job.how to do this?Give me command?
How do you start developing a datastage project?
How to read multiple files using a single datastage job if files have the same metadata?
what are the types of nodes
Where do you see different stages in the designer?
Input file one has data as shown below 1 2 3 4 5 6 7 8 Input file two has data like 6 7 8 9 10 11 Design a data stage job which will provide me three output files as shown below: Output 1 6 7 8 Output 2 1 2 3 4 5 Output 3 9 10 11 Let me know your answers
what is ds administrator used for?
what are fact tables and dimension tables? give example assuming one table.
how to find diff between 2 dates without using Icon... funtions?
When we will go for Data elements?
How many nodes supported by a one cpu in parallel jobs?
wt is the difference between swith and filter stage
Teradata 
