Multi-Table Inserts with Sequences

Multi-table inserts are a drag when sequences are involved, because we don't have enough control over when the sequence is incremented. I've seen some dangerous workarounds. Here is a workaround that I think is safe.

jmeter – Variable Name must not be null in JDBC Request

So Jmeter seems super cool.

I’ve only used it a little bit but it does seem a bit touchy about somethings (like spaces in input fields) and the errors are often less than obvious and I’m not finding that much out there on google for the errors.

Today I ran into the error

Variable Name must not be null in JDBC Request



and Googling it didn’t turn up anything.

I’m pretty sure I ran (more...)

Disappearing Data

Did you know that Oracle DML can silently change data you want to put into the database? A recent twitter discussion started by Martin Widlake (@MDWidlake) prompted me to study more closely what happens when.

jmeter – getting started

This blog post is just a start at documenting some of my experiences with jmeter. As far as load testing tools go, jmeter looks the most promising to me. It has an active community, supports many different databases and looks quite flexible as far as architecting different work loads goes.

The flexibility of jmeter also makes it hard to use. One can use jmeter for many other things besides databases so the initial set up (more...)

Graphics for SQL Optimization

Dan Tow, in his book SQL Tuning, lays out a simple method of tuning SQL queries. The method is

  • Draw a diagram of each table in the query with Children above Parents
  • Draw join lines between each join (many-to-many, one-to-many)
  • Mark each table with a predicate filter and calculate the amount of table filtered out

Then to find a great optimal optimization path candidate

  1. Start at the table with the strongest predicate filter (the (more...)

Dealing with a global increase in CPU usage

Imagine the following situation: you are supporting an application with many different components and a busy release cycle. One a Monday morning you find that quite a few processes in the database now run slower. Very soon, you find out that the slowdown is due to increased CPU time, but where to move from there? There is no evidence that CPU is too stressed, causing CPU queuing. You cannot isolate the problem to any specific PL/SQL (more...)

Apple Upset – upgrading to iPhone 7

Upgrading is always stressful – be it a computer, an Oracle database or an iPhone. There’s always a good chance for lost data and lost time dealing with complications.

So yesterday I picked up a new iPhone 7 from Verizon. The pickup was seamless. I had signed up for an upgrade program when I got the iPhone 6, so now I just walked in, gave them my old iPhone 6 and they gave me an (more...)

Oracle Mediator, the-always-give-response-pattern by using the Echo-reply

In my usecase i subscribed to an eventbus solution (rabbitmq with some custom code to be able to publish to consumers based on the soap protocol).

The backend system which generated the notications can generate the next type of events :

— employeename got changed

<nce:notification xmlns:nce="http://my.notifications" xmlns:xsi="">

— employee contactaddress got changed

<nce:notification xmlns:nce="http://my.notifications" xmlns:xsi="">

The current subscription mechanism only allows me (more...)

Why does my full table scan take 10x longer today ?!

Every so often a DSS query that usually takes 10 minutes ends up taking over an hour.  (or one that takes an hour never seems to finish)

Why would this happen?

When investigating the DSS query, perhaps with wait event tracing,  one finds that the query which is doing full table scans and should be doing large multi-block reads and waiting for “db file scattered read” is instead waiting for single block reads, ie (more...)

Rename Pluggable Database

I stumbled upon a convenient way to rename a pluggable database:

SQL> alter system enable restricted session;

System altered.

SQL> alter database rename global_name to;

Database altered.

SQL> alter session set container=cdb$root;

Session altered.

SQL> select name from v$pdbs;


In other words, to rename a pluggable database, one only needs to rename its global name. Cute!

Amazon announces Performance Insights

Excited to see the announcement of Amazon RDS Performance Insight feature for database performance monitoring and tuning.

Having met the team for this project I can say from my personal view point that the importance and future success of this feature is clear as day to me. The team is awesomely sharp, the architecture is super impressive, and this is by far the most exciting performance monitoring and feedback system I’ve been involved with,  surpassing the (more...)

#DOAG2016, definitely a crazy week.

#DOAG2016, the largest Oracle Community gathering in Europe. Taking place in Nuremberg, at the Nuremberg Convention Center NCC, one of the more impressive places to hold such a conference, towering 4 stories high, with a big central atrium!!
It is a huge effort to get all of this together!

In this blog-post I want to highlight some of the crazy things I experienced this week… And… I did try to follow my own schedule (more...)

Configure Oracle EBS integrated soa gateway for SOAP services on 12.2.6

Here I am going to explain how to configure Oracle EBS integrated soa gateway for SOAP services on 12.2.6.

The E business suite integrated soa gateway configuration require a Oracle SOA suite  with weblogic on separate server.

Refer the document for how to install

Installing Oracle E-Business Suite Integrated SOA Gateway, Release 12.2 (Doc ID 1311068.1)

In this note, Go to

Section 1: Configuring Oracle E-Business Suite Integrated SOA Gateway for (more...)

#DOAG2016: Bug !

I did it: in my proudest moment at DOAG2016, at the very end of my second presentation, I presented a brilliant SQL query with a bug in it. After agonizing for awhile, I finally saw that the correction was simple and didn't change the timing.

User ASADMIN does not have the privilege of deploying/undeploying composites

I am trying to deploy the SOAP service in ebs 12.2.6 with integrated SOA gateway. I can able to deploy the wsdl file but I can’t able to view wsdl files. The below error appeared when I try to open view wsdl file

“Failed to Load a composite for composite identified by default”

So I realized  the error seems to be part of SOA server. I looked the SOA server log from EM (more...)

Oracle Maven Repository in Nexus, authentication failure

Short overview of some last week failing builds at our site 😉

Since a while ago it’s possible to register proxy repositories in Nexus based on the Oracle Maven Repository.
To be able to proxy this repository you need to make use of an oracle account for the autenthication before you can download the artifact.

Let’s check the logging to understand what it does (i can rephrase the logfile or just copy/paste it ;), when others (more...)

Signing up for scary stuff

So I subscribe to the idea that the only way to improve is to dive in on the deep end. Sink or swim.

With that in mind I sent in an abstract to RMOUG and actually got it accepted. Now, this is a conference I used to attend every year when I lived in Denver. I know the quality they have in most presentations nad I know that lots of people with “important” names in the (more...)


Oracle 12c has a new feature related to optimizer dynamic sampling. The new level 11 is supposed to put the dynamic sampling on auto pilot and make the statistics available to other users. However, as soon as this was set, I started noticing processes spending significant time waiting for row cache latch. This was strange, especially having in mind that ASMM was configured. I checked the V$ROWCACHE  by using the following, fairly standard, query:

select (more...)

ORA-01157: cannot identify ORA-01110: data file with dba_temp_file

                                 Recently one of our database was migrated. After migration DB is up and running, But we found below errors in the alert log.


Errors in file /oracle/app/oracle/admin/test/diag/rdbms/b2btrn/TEST/trace/test_ora_20464.trc:
ORA-01157: cannot identify/lock data file 205 – see DBWR trace file
ORA-01110: data file 205: ‘/test/oradata/b2btrn/tempfile/temp1.304.921456819′

Now I queried dba_temp_files, and got the same error.


SQL> select (more...)

October Webinar Series: Digital Transformation, Forms and Mobile

This year’s Oracle Open World was an exciting experience for AuraPlayer, with many flocking to our booth for live demos and attending Mia’s sessions with clients like Rogers Group Inc. We were sad that many were unable to attend the conference, so we are bringing Oracle Open World to you in our October webinar series!

In the first installment of this series, “Digital Transformation: From Legacy to Enterprise Mobility,” we will demonstrate step-by-step how best (more...)