When massaging large volumes of data into your datawarehouse, it is necessary to give the database the maximum resources available to get the job done in time. Our setup consists of a 2s12c24t blade with 48G of memory running Oracle linux 5.7 with a 22.214.171.124 database. (more...)
I know no one really likes the term “tuning” these days, but it’s a short catchy word that gets the idea across. So I’ll just stick with it for the title of this post.
Note that this is one of those posts that’s not really supposed to be about how to solve a particular problem. It’s really just a story about a distraction that I ran into and I how I thought about getting around the issue and then ultimately resolving the root cause. Maybe you will find it instructive to see the process.
So I have this script that (more...)
Original Post can be viewed at Poll on Sql Plan Management
Dominic is conducting poll on SPM and Sql Profiles usage on his website. Link can be found here I have been using SPM and SQL Profiles (using coe_xfr_profile.sql) to fix plans for queries and believe me its very easy and quick way of fixing problems in production database. I have not yet used SPM to [...]
|Ver este articulo en Español|
This is THE MySQL performance book. Period!
|Ver este articulo en Español|
During the past week I had the opportunity to assist both the Oracle Performance Firefighting and the
Advanced Oracle Performance Analysis and only can say: awesome!!!
Craig Shallahamer is a great teacher and has a lot of resources to effectively share knowledge, even if
the subject is complex like buffer cache structures or arid like the mathematical foundation required for
perf analysis. That is not all, he provides valuable tips of the trade or anecdote nuggets, dipped on a
very fresh and sometimes humorist perspective.
The result: we started searching for those (more...)
Tuning has always being good fun and something like a challenge for me.
From time to time we are being asked to find out why something did run slow while you are sleeping; answering this question is, in most cases, a challenge.
My batch did run slow last night, can you let us know why? Or why did this query run slow? Are questions we, as DBAs, have to answer from time to time.
Oracle has provided us with many tools to dig out information about past operations. We have EM, AWR, ASH, dba_hist_* tables, scripts (more...)
A SQL statement can be executed in many different ways, such as full table scans, index scans, nested loops, and hash joins. The query optimizer determines the most efficient way to execute a SQL statement after considering many factors related to the objects referenced and the conditions specified in the query. This determination is an important step in the processing of any SQL statement and can greatly affect execution time.
PLANresults let you determine whether the optimizer selects a particular execution plan, such as, nested loops join. It also helps you to understand the optimizer decisions, (more...)
SQL Developer support several types of tuning activities. These are:
- Explain Plan/ Autotrace and Diff
- Monitoring SQL
- SQL Tuning Advisor
- PLSQL Hierarchical Profiler
I regret not being able to write new things more often, but in fact it only means I am OK: very busy with work, doing private stuff (which is important since life is not all about working), enjoying the three young kids and trying to achieve some good results in track and field. And for that last goal, I can say I did. After a few months of struggling to find a tiny piece of shape comparable to last years shape, just in time I found it. I won the gold medal in the Dutch Championships 400 metres hurdles. OK, be (more...)
Recently, I wanted to work out the maximum value of a column on a partitioned table. The column I wanted the maximum value for, happened to be the (single and only) partition key column. The table in question was range partitioned on this single key column, into monthly partitions for (more...)
My primary skills are in troubleshooting and tuning Oracle systems, from entire databases to individual SQL queries.
If you have an application running on an Oracle database and you need someone to investigate an issue on that system, get in touch.
"My name is Peter Moore. I am a professionally qualified and highly experienced database administrator with extensive (more...)