Today’s venue was the Metropole Hotel in the centre of Leeds and there was a good attendance, encouraged by a strong agenda.
After introductions, health and safety and UKOUG information it was straight into techie talk with Phil Davies from Oracle doing his normal support update (although he does share duties with Owen Ireland). Invariably I make more notes from this session than most others I hear because of the wealth of information it contains. Snippets I jotted down that are worthy of sharing are :-
Today I am going to mention two articles which I came across in the last few days whilst investigating problems and talk about the background to the problems but also praise the articles. I am sure many of us have run the SQL Tuning advisor from within OEM or using the DBMS_SQLTUNE package from the command line and often it recommends a sql_profile that should be applied, (invariably giving 99.98 perceived benefits). Now I see this as both a good thing and a bad thing.
Just a quick entry to show the use of a command that I had forgotten existed but it seemed to work nicely
Problem – OEM12C agent had been down for a few days on a non-production server and more than the maximum number of files had been created ready to be uploaded.
emctl status agent
It is well known that poor performance on the standby server of a DataGuard pair can affect the performance of the primary database. This post shows an example and how to use the view GV$EVENT_HISTOGRAM to track down an issue.
The databases were 126.96.36.199 on HPUX. I had been seeing alerts from OEM to state that the standby was seeing lag_apply delays when applying redo to standby. Looking at the primary database alert log I could see the entries
Please be aware of the serious bug identified with RMAN duplicate database on the same node with versions 188.8.131.52 and 184.108.40.206
This note gives a brief overview of bug 13498382.
The content was last updated on: 07-FEB-2014
Click here for details of each of the sections below.
We had a requirement to perform a one-off update on a table of around 1.2M rows. There were 11K statements similar to the one below, with varying values and predicates updating a variety of rows from 20 to 500. The potential elapsed time was around 44 hours due to the volume of full table scans involved.
The obvious thing to do was to create an index but this was production and it was urgent so no time to go through the full route to live test cycle.
Oracle restart is an 11GR2 feature which ensures that all services on a standalone installation start up in the correct order. As such it seems to work well. One bugbear I have with it is that it changes the order of entries in the /etc/oratab file. Personally I like my oratab to be ordered in terms of database (most used first), ASM, then agents. In that way when I logon to a box and it automatically sets the SID it picks up the first entry which is commonly the database I want to work with.
As this the traditional time to layout resolutions for the year here are my 2 database related ones.
To understand more about some of the newer technologies and to advance my use of APEX as a means of providing reporting information around the systems and people I manage.
At the end of the year WordPress produce a brief analysis of activity on my blog
The Louvre Museum has 8.5 million visitors per year. This blog was viewed about 160,000 times in 2013. If it were an exhibit at the Louvre Museum, it would take about 7 days for that many people to see it.
In 2013, there were 25 new posts, growing the total archive of this blog to 176 posts. There were 32 pictures uploaded, taking up a total of 5 MB. That’s about 3 pictures per month.