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Most administrators are now aware of the lockdown profile facility in the Oracle database (available since 12c). They allow a more granular level of privilege control of components and functionality within the database. I’m not going to spend more time than that on what they do – this post is just to highlight a small “gotcha” that you need to be aware of when farming out lockdown profiles to pluggable databases.

For example, perhaps one your pluggable databases should not be using UTL_HTTP and you’ve created a lockdown profile called “P1” to handle that. You would then set that profile at the PDB level via something such as:

In the previous post, I described the importance of checking V$IM_SEGMENTS to ensure that the in-memory store is populated to have confidence that you are indeed getting the benefit of the feature. But even if the store has been populated, when it comes to virtual columns, additional care is needed to make sure you can take advantage of the feature. Here is an example of how you might not be getting the in-memory benefits when you were expecting to (and how to solve it).

I’ll start by creating a table T as 20 copies of DBA_OBJECTS, and I’ll add a virtual column called OBJECT_DETAILS. The definition for the virtual column is somewhat nonsensical, being many nested SQRT calls, but this also makes it easy to check for in-memory usage (as I’ll explain shortly).

First of all … Happy New Year! This is my first post for 2020. Last year, I fell just short of 100 blog posts for the year – so this year, I’m starting early and hopefully I can crack the 100 mark! Anyway..onto the post.

The in-memory option in the Oracle database can yield some ridiculously good performance results. As someone who regularly gets to visit customers, it is always a feel good moment when you can take their data warehouse sample data and queries, which could be running in minutes or hours, slap on some in-memory parameters and watch the amazement when those queries might drop from hours to minutes, or minutes to seconds.

VirtualBox 6.1 was released on the 11th of December and I totally missed it.

The downloads and changelog are in the usual places.

I spotted it this morning, downloaded it and installed in straight away. I had no installation dramas on Windows 10, macoS Catalina and Oracle Linux 7 hosts.

A quick tip just in time for Christmas

I logged on to my database this morning, and things just didn’t look right. In fact, they looked down right alarming. All my objects were gone, my user account had the wrong password..It was almost as if I was connecting to a totally different database!

That’s because I was! Here is how it happened:

If you take a look at the log files created by the listener, there is obviously a nice wealth of information in there. We get service updates, connections etc, all of which might be useful particularly in terms of auditing security

However, it also is in a fairly loose text format, which means ideally I’d like to utilise the power of SQL to mine the data.

Just a quick tip that often catches me out. If you are like me, you have long since tired of clicking Next, Next, Next, … through the GUI when you want to quickly create a database. Many people work around this by storing a set of database creation scripts. However, you can do even better. The Database Creation Assistant (dbca) can also be used at the command line and in silent mode.

On Windows, this is the error I commonly get when using dbca at the command line

In today’s video we take a look at RESTful web services handling media files built using Oracle REST Data Services (ORDS).

This is based on this article.

• Oracle REST Data Services (ORDS) : RESTful Web Services Handling Media (Documents and Images)

There is more information about related stuff here.

Here are the blog posts that you hit on most this year, with the most viewed entry on top. Unsurprisingly is it related to my bugbear with the OpenWorld catalog. I mean, every conference organizer must know that the one thing the attendees will always want is to get access to all of the content. Questions on UTL_FILE often come up on AskTOM, so it is unsurprising to see UTL_FILE pop up on the list.

We had a question on AskTOM inquiring about how to handle the issue of only 8 storage indexes being possible on an Exadata engineered system. If you are unfamiliar with what a storage index is, they are part of the suite of features often referred to as the “secret sauce” that can improve query performance on Exadata systems by holding more metadata about the data that is stored on disk. You can get an introduction to the concept of storage indexes here.