I just created a one-page APEX application to show performance chart of our main production server based on Active Session History data. We publish it on a big monitor so we can see the performance chart during the day. It’s not a big deal but it’s really useful. I used 2D stacked column chart and make the chart simple (contains only 3 colors: green for CPU, blue for user IO and orange for all other (more...)
Oracle Database 12c brings us many new features including: the long needed ability to run OPatch and query the patch software installed in the Oracle Home programatically through SQL using the new DBMS_QOPATCH package.
If you’re a DBA working in an environment where patching consistently among databases is important, this is a welcomed enhancement. Sometimes one-off critical bug fix patches are important in the environment. Other times regular and consistent application of the quarterly (more...)
I Have Lots Of Oracle Database Server Power But Performance Is Slow/Bad
But performance is unacceptable; users are screaming, the phone is ringing, and those fancy dashboards are flashing like it's Christmastime.
What is going on?! What can I do about it?! That's (more...)
After my issues with the patch bundle some of my database targets ended up in an odd ‘Status Pending’ state. I received this guidance from RachelB on the OTN site for OEM Community at
“The database system target is one of those targets that has it’s status evaluated in the repository. Normally if the status is not changing, it’s a good idea to check the internal repostory (dba scheduler job) which (more...)
Here is the link: url
It looks like our meeting tomorrow will be on Oracle 12c new features. I’m looking forward to participating.
In an earlier post (not very serious) post about count(*) I pointed out how the optimizer sometimes does a redundant bitmap conversion to rowid when counting. In the basic count(*) example I showed this wasn’t a realistic issue unless you had set cursor_sharing to force (or the now-deprecated similar). There are, however, some cases where the optimizer can do this in more realistic circumstances and this posting models a scenario I came across a few (more...)
This is a write-up of an issue I recently posted to the OTN discussion forum (https://community.oracle.com/message/12798407). I thought the associated test case was useful in demonstrating the issue, so is captured here for future reference. There were some useful replies to the OTN post, confirming my suspicions.
The test was performed using Oracle Enterprise Edition 126.96.36.199.0 on Linux.
A parallel delete blocks insert into dependent (more...)
Sync tables: generate MERGE using Unique constraint.
What Hardware and Software Do YOU Want Oracle to Build?
There were a number of new features introduced in Ops Center 12.2.2. One of the shiny ones is an expansion of the backup and recovery capabilities to include Proxy Controllers.
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Performance schema, as name suggest is a tool for monitoring MySQL performance. It was implemented staring from MySQL 5.5 and improved further in MySQL 5.6. Performance Schema includes set of tables that gives information on how database is performing. It provides a way to inspect internal execution of the server at run time. Performance schema monitors every “event” the server does that takes time and has been instrumented so that timing information can (more...)
There are a couple of things on the radar for the coming week and unfortunately for me they are both on the same day.
In Birmingham, UK it is Oracle Midlands Event #7 (OM7) on Thursday 22nd of January. This will be the first Oracle Midlands event I’ve missed since it started. I’m a big fan of what Mike is doing with Oracle Midlands and I appreciate the sponsorship from Redgate that means it is (more...)
The quality of the presentations at NoCOUG conferences is truly exceptional. Consider, for example, these exceptional presentations by the eBay/PayPal database engineering team at the last conference.
- Managing a Large OLTP Database (How PayPal copies with the complexities of its Oracle database environment)
- Database Platform Selection Tool (How PayPal decides which database technology is best suited for a particular use case)’
- Sharding Oracle Databases (How to shard your data even if Oracle Database does not (more...)
Join me on Wednesday, January 28th at AllThingsOracle.com for a session based on a real world customer experience.
The session starts at 3pm UK (16:00 Central European) time. The webinar is totally free and the recording will made available afterwards.
Here's the link to the official landing page where you can register and below is the official abstract:
AbstractAfter a short introduction into what the Oracle Exadata Database Machine (more...)
It's the usual deal at the Rockside Road Oracle office so free lunch at noon and networking opportunities. Meeting starts at 1 pm.
Our March meeting will be (more...)
I’ve had a few folks ask me a similar question about the AWR Warehouse, occuring numerous times this week.
“How can I limit what the user of the AWR Warehouse can view in the AWR Warehouse?”
“How can I add source databases to the AWR Warehouse without DBA privileges?”
This topic bridges into the area of confusion of use of the EM12c environment, (which I consistently promote for use by DBAs, Developers (more...)
Oracle has come up with new feature called multitenant database. Using this feature we can have many pluggable databases plugged into single container database.
This article explains pluggable databases architecture and how to create them.
I am not covering administration part. Viewers can check the documentation mentioned in reference section to check administrative part for managing pluggable databases.
One of the high-profile new features of Oracle 12c Enterprise Edition(EE) is the multitenant option (more...)
One thing you (ought to) learn very early on in an Oracle career is that there are always cases you haven’t previously considered. It’s a feature that is frequently the downfall of “I found it on the internet” SQL. Here’s one (heavily paraphrased) example that appeared on the OTN database forum a few days ago:
select table_name,round((blocks*8),2)||’kb’ “size” from user_tables where table_name = ‘MYTABLE';
select table_name,round((num_rows*avg_row_len/1024),2)||’kb’ “size” from user_tables where table_name = ‘MYTABLE';
The result from (more...)
Just a short post on a problem I encountered recently.
I had to install 11.2 GI and right after running the installer I got a message saying permission denied. Below is the exact error:
[oracle@testdb grid]$ ./runInstaller -silent -showProgress -waitforcompletion -responseFile /u01/software/grid/response/grid_install_20140114.rsp Starting Oracle Universal Installer... Checking Temp space: must be greater than 120 MB. Actual 7507 MB Passed Checking swap space: must be greater than 150 MB. Actual 8191 MB (more...)