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Virtual Private Database: Beyond the Basics

Virtual Private Database (VPD), also referred to as row-level security or RLS, is a feature built into the Oracle Database that allows you to set up security policies on tables that restrict which rows a user can see or change based on the policy logic.

One of the nicest things about VPD is that this logic (and the fact that a filter is being applied) is completely invisible to the user. They just see the data relevant to them and none the wiser about all that other data in the data.

Here's a simple example to drive the point home: suppose I am building a health care application and it contains a patients table. The security policy is straightforward:
  • A patient can only see their own information.
  • A doctor can see only the information about their own patients.
  • A clinic administrator can see information only about the patients in their clinic.
In all three cases, the user would sign on to the application and execute this identical query and only their rows would appear.

SELECT * FROM patients

Of course, there are lots of different and very interesting aspects to setting up your policies. Back on March 3, 2020, Praveen Kumar of Wipro shared his thoughts about VPD with 100 developers on PL/SQL Office Hours.

He ran out of time before he could explore some of the more interesting challenges and beyond-the-basics features, so we are bringing him back on May 5th at 11 AM Eastern to complete his thoughts! We hope you'll join us. We encourage you to watch last session's video beforehand to get the most out of the May session.

Our Presenter: Praveen Kumar of Wipro

Parveen Kumar is a Java and Oracle Developer with Wipro, based in the UK. He has over eight years experience focused mainly on developing and designing applications using Oracle Database as a primary database. He aims to keep the business logic inside the database and expose data through PL/SQL APIs.

Parveen has in various projects taken advantage of native support for XML, JSON and Object datatypes, SOAP/REST APIs for Web Programming and security features like VPD/RLS, Oracle Wallet for Web APIs and other features which provide true fine grained access to different types of users.

In the May Office Hours session, Praveen will cover these topics and maybe even some more:
  • Policy Groups and how they work and provide better control
  • Application roles in conjunction with VPD more detail
  • Performance issues and analyzing and fixing them
  • Drawbacks and real-time challenges of working with VPDs 
  • Maintenance of VPD policies
Follow this link to subscribe to my monthly PL/SQL Office Hours program, so that you will receive email reminders for this and future sessions.

You can also view recordings of the dozens of past sessions, including:


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