All entries for Thursday 15 July 2004

Courses best for getting a job

Hongfeng Sun : 15 Jul 2004 16:32 |  Tags: Article |  Comments (1) |  Close comments |  Report a problem

Second Step in Oracle Certification Ladder

Follow-up to First step in oracle certification ladder from Oracle/Java/Others

Today I passed the "Oracle9i DBA Fundamental II" test at very high score. I got 61 out of 63 scored items!
I did not expect such good result at all.

In the test I experienced nerviousness, relaxation, uncertainty, doubt, anticipation, and jubilancy.

So that test concluded my whole certification test process for Oracle Certified Database Adminstrator ( OCP ), which contains 4 tests altogether and 8 months hard study.

I must say the certification test is not easy at all and require careful study and plenty practice. From now on, I will have free time at night and more acoompany to Selina.

Joy !

Hongfeng Sun : 15 Jul 2004 15:30 |  Tags: Oracle |  Comments (3) |  Close comments |  Report a problem

Controlfile Restore

When online redo is lost and datafile is current, use CREATE CONTROLFILE; Otherwise resotore controlfile.

Hongfeng Sun : 15 Jul 2004 11:03 |  Tags: Oracle |  Comments (0) |  Close comments |  Report a problem

Cache Recovery and Transaction Recovery

The following two phases happens during instance recovery

Cache Recovery (Rolling Forward)
Transaction Recovery (Rolling Back)

To impreove cache recovery, set RECOVERY_PARALLELISM >1

To improve transaction recovery, set FAST_START_PARALLEL_ROLLBACK = [ high | low | false ].
Low specifies that the number of recovery servers cannot exceed twice the value of the CPU_COUNT initialization parameter.

v$fast_start_servers provides information about all recovery processes performing fast-start parallel rolback.
v$fast_start_transactions contrains data about the progress of the transactions

SMON is responsible for roll-forwarding, not RECO.
RECO is used to resove distributed transactions that are pending due to network or system failure

Update:

I killed one big deletion DML once. The transaction roll back took huge amount resource and database hung.
Significant waits for “Wait for a undo record” and “Wait for stopper event to be increased”.

I have to change FAST_START_PARALLEL_ROLLBACK = FALSE.

See Doc 464246.1 and blog here

25/01/2012

Hongfeng Sun : 15 Jul 2004 10:40 |  Tags: Oracle |  Comments (0) |  Close comments |  Report a problem