Thank you all for attending, commenting and discussing my presentations at DOAG Konferenz 2021. I am happy about the good feedback, and the attendance in the rooms. Meeting some of you in DOAG’s GatherTown was a good thing, to mimic the real conference center in Nuremberg. But still a mimic! I’m looking forward to DOAG […]
Category: Performance
Very cool interview with Maria Colgan
Community work can be so much fun. When working for the German Oracle User Group, DOAG, one of my favourite jobs is interviewing interesting people for doag.tv. In fall 2019, we recorded a fun interview with Maria Colgan, Master Product Manager for the Oracle Database. I had the chance to prepare the story: Based on […]
Oracle PGA Analysis Query
Sometimes, something in an Oracle Database starts eating PGA, and there is need to find out which process, and where the memory is left, and what or who is responsible for allocating / using / holding it. For a recent issue, I wrote the SQL below. It gives back one line for each Category (SQL, […]
ORATOP in Oracle 19c
In 19c , the useful utility “oratop” is shipped with the Oracle Home installation. It was linked to the recent libaries, and its command line syntax changed. Error This leads to errors when calling one of the old “download” binaries like oratop12c-64.bin in a 19c environment: /home/oracle/bin/oratop12c-64.bin: error while loading shared libraries: libclntshcore.so.12.1: cannot open […]
Oracle: Create a Materialized View with Fast Refresh on commit and debug upcoming errors
Sometimes, our users and customers need rapid access to complex data structures. Materialized Views in their various forms are a very potent way to shift efforts from the query to insert/update time of base data. That’s the nature of a Materialized View: One way or another, we need to put the data into a redundant structure. With […]
Restarting Oracle for Performance is like a Coitus for Virginity
Today I had another case of that … total breakdown of a live environment by infrastructure defect, bad enough. Customer rushing up the database and all apps services, just to see thousands of locks and hanging transactions. Big panic, frequent restarting of databases and applications. Getting worse, finally calling me. Told them I’ll manage that, asked […]
Oracle: How to identify SQL doing TABLE ACCESS FULL on a given partition
In my last post, I described a quick show case for Oracle 12c Automatic Big Table Caching. But ABTC is just a crock, nevertheless a useful one. The biggest help from Automatic Big Table Caching for “sustainable” database performance management is the temperature of segments, heated up by TABLE ACCESS FULL. In my case, after enabling ABTC […]
Oracle Automatic Big Table Caching – an improvement, not a fix
Too much TABLE ACCESS FULL in your Oracle Database? Thus, SQL elapsed time too slow for the demand? Plenty of Buffer Cache to create a temporary fix? maybe you want to consider Automatic Big Table Caching. Usually, Oracle only does Full Table Caching for small tables. Big ones will only use the Buffer Cache for the current chunk […]
Oracle SQL showing current expensive queries plus most expensive object from execution plan
Sometimes, it’s useful to see what’s currently going on in your Oracle Database. This query is meant to help with this task, that haunts every DBA from time to time. It’s just using v$sql and v$sql_plan, so no need for Enterprise Edition and Diagnostics Pack. Key features: find top buffer getters per execution from v$sql […]