Computer Tutorials
Earn Money From Internet
Cheap Freelancers
Ask An Expert
Register Cheap Domain
Data Recovery
Best Mutual Funds
Trading Forex Online
Cheap Web Hosting
Ajax Tutorials
Cheap Cell Phone Plans
Free Mobile Learning
Job Portal
Photoshop Tutorials
Cheap Jewelry
Cheapest Air Travel
Oracle Interview Questions And Answers
|
Page 21 of 95
32. How will you monitor the space allocation ? By quering DBA_SEGMENT table/view. 33. How will you monitor rollback segment status ? Querying the DBA_ROLLBACK_SEGS view IN USE - Rollback Segment is on-line. AVAILABLE - Rollback Segment available but not on-line. OFF-LINE - Rollback Segment off-line INVALID - Rollback Segment Dropped. NEEDS RECOVERY - Contains data but need recovery or corupted. PARTLY AVAILABLE - Contains data from an unresolved transaction involving a distributed database. 34. List the sequence of events when a large transaction that exceeds beyond its optimal value when an entry wraps and causes the rollback segment to expand into another extend. Transaction Begins. An entry is made in the RES header for new transactions entry Transaction acquires blocks in an extent of RBS The entry attempts to wrap into second extent. None is available, so that the RBS must extent. The RBS checks to see if it is part of its OPTIMAL size. RBS chooses its oldest inactive segment. Oldest inactive segment is eliminated. RBS extents The Data dictionary table for space management are updated. Transaction Completes. 35. How can we plan storage for very large tables ? Limit the number of extents in the table Separate Table from its indexes. Allocate Sufficient temporary storage. 36. How will you estimate the space required by a non-clustered tables? Calculate the total header size Calculate the available dataspace per data block Calculate the combined column lengths of the average row Calculate the total average row size. Calculate the average number rows that can fit in a block Calculate the number of blocks and bytes required for the table. After arriving the calculation, add 10 % additional space to calculate the initial extent size for a working table. 37. It is possible to use raw devices as data files and what is the advantages over file. system files ? Yes. |