There’s a current question on the OTN database forum as follows (with a little cosmetic adjustment):
I have a request for 3 indices as shown below. Does the 1st index suffice for 2 and 3? Do I need all 3?
- create index idx_atm_em_eff_ver_current_del on atm_xxx_salary (employee_key, effective_dt, salary_version_number, is_current, is_deleted);
- create index idx_atm_em_ver_current on atm_xxx_salary (employee_key, salary_version_number, is_current);
- create index .idx_atm_sal_current_del on atm_xxx_salary (employee_key, is_deleted, is_current);
In the absence of any information (more...)
This was the statement:
from CLIENT k
where k.expires is null;
I've used fake names for table name and columns.
Database version: 22.214.171.124.0
Indeed, query was running longer than I would expect. Oracle was using FULL SCAN of the table with "db file sequential read" wait events. This was little odd (more...)
Understanding the workload is an important part of troubleshooting activities. We seek answers to questions like: what is the system doing, where is the time spent, which code paths are most used, what are the wait events, etc. Sometimes the relevant diagnostic data is easy to find, other times we need to dig (more...)
As usual the latest version can be downloaded here.
The v$log_history view contains important information on how application’s users use the database , this view can help you define periods with the most activity in the database. v$log_history queries You can adapt the query to your needs, you just have to change the way you format the date to be able to drilldown to the … Continue reading Analyze database activity using v$log_history
A rather not so great post about an ORA-00600 error i faced on a standby database. Environement was 126.96.36.199 on Sun Super Cluster machine. MRP process was hitting ORA-00600 while trying to apply a specific archive log.
The error message was something like this
MRP0: Background Media Recovery terminated with error 600 Errors in file /u01/app/oracle/product/188.8.131.52/diag/diag/rdbms/xxxprd/xxxprd1/trace/xxxprd1_pr00_6342.trc: ORA-00600: internal error code, arguments: , , , , , , , (more...)
This was virtual machine running oldish 10.2.0.5.0 Oracle database.
I noticed that backup for my database is failing because of archive log corruption. As this is development database I've simply deleted corrupted archive logs and initiated full backup again. But backup (more...)
- The .AET trace file can now include the PeopleCode trace. This removes the need of checking the .AET file for the the non-PeopleCode steps and the .TRC file for the PeopleCode steps. Surely, .TRC files (more...)
One of the great things about working in IT is that you can often win an argument simply by being right. Not because of who you are or because you are more eloquent than others, but because the facts support your position. Almost every IT person I have ever met respects facts.
In order to win arguments this way, you of course need some facts to work with. And that’s where too many people fail. (more...)
I wanted to install Oracle JDevelper 12.1.3 – a version that I had been eagerly awaiting. Since my primary machine is a MacBook, I wanted to install it on OS X 10.9.3.
I downloaded the generic installer and found that the install didn’t run. Since OS X had disappeared from the documentation, I assumed that I would have to fiddle around until I found a combination of JDK and OS (more...)
I noticed something for the first time tonight when I was playing around in the Enkitec lab – something that I have been doing wrong for a while. When working in the lab, I often rely on the crsctl command to shut down the entire cluster stack for me. It’s really easy to use “crsctl stop cluster -all” followed by “dcli -l root -g ~/dbs_group /u01/app/184.108.40.206/grid/bin/crsctl stop crs” to get everything down (more...)
We had a client that was running into a strange issue on their Exadata where new connections coming in through the SCAN were failing. After doing some troubleshooting, it was discovered that it was related to one of the SCAN listeners not properly accepting requests from new sessions. The VIP and listener were running, and everything looked normal.
We had the following SCAN setup:
|SCAN VIP #||VIP IP|
Special thanks to my colleague who spotted odd results which led us to this finding.
My test (virtual) environment is:
OS: Oracle Enterprise Linux 5.8
DB: Oracle EE 220.127.116.11.12
In test I (more...)
In the Oracle technical universe, it seems that the end of the calendar year is always eventful. First there’s OpenWorld: obviously significant for official announcements and insight into Oracle’s strategy. It’s also the week when many top engineers around the world meet up in San Francisco to catch up over beers – justifying hotel and flight expenses by preparing technical presentations of their most interesting and recent problems or projects. UKOUG and DOAG happen shortly (more...)
rman target /
Recovery Manager: Release 18.104.22.168.0 - Production on Wed Sep 18 20:47:38 2013