​In this post I will demonstrate a useful feature of APEX that does not get a lot of attention. ‘User Preferences’. It’s another one of those APEX features that saves you time. This allows you to focus more time on building important business logic that adds value to your business.

APEX User Preferences allow you to store name value pairs by user and APEX application. These name value pairs are persisted using an internal APEX table. You can set, get and delete user preferences declaratively or via APEX provided APIs.
 
You can imagine these name value pairs are stored as follows:

There are many reasons why you may want to store values related to a particular user:

• Default Time zone
• Default language
• Notification preference
• Default home screen
• Default unit of measure
• URL to profile picture
• etc.

​For the remainder of this post, I will demonstrate how to get and set preferences using a simple example. In this example, we have a user preference which determines if the user sees a Detailed or Summarized dashboard view when the user logs in.
 
Here is a screen shot of the a sample preferences page which I created where the user can set their default dashboard view.

​There is no need to formally create a user preference before setting a value for it. When you set a user preference for the first time, APEX creates a record in an internal table to store the preference and its value. This value is stored until you either change or delete the preference.
 
There are two ways to set a preference value.
 
1. Declaratively in a Page Process
One of the great things about user preferences is that you can set a user preference declaratively (no code) using a page process. The below page process is set to run when the user clicks the ‘Apply’ button (from our example above). When it runs, the user preference ‘DASHBOARD_VIEW’ is set to the current value of the page item ‘P3_DASHBOARD_VIEW’. 

​The key here is the type ‘User Preferences’ (under the ‘Identification’ section).
 
The type under the ‘Settings’ section has three options, two of which (in bold) can be used to set a user preference. Their names are pretty self-explanatory.

• Reset Preferences (remove all preferences for current user)
• Set to Item Value
• Set to Item Value if Not Null

More about the first option later in the post.
 
2. Programmatically Using an API
APEX also provides and API which you can use to set User Preferences. In the below code snippet, we are setting the user preference ‘DASHBOARD_VIEW’ to the value ‘DETAILED’ for the currently logged in user.

​There are also two ways to get a preference value.
 
1. Declaratively Using Page Item Source
You can declare the source for a page item to be a User Preference (again no code). This means that when the page is rendered, the page item automatically picks up the value for the preference.

​In our example, we need to initialize the item ‘P3_DASHBOARD_VIEW’ with the current value for the user preference ‘DASHBOARD_VIEW’.
 
2. Programmatically Using an API
APEX also provides and API which you can use to get the value for a user preference. In the below code snippet, we are getting the current value for user preference ‘DASHBOARD_VIEW’ for the currently logged in user.

​It may not be completely necessary to purge user preferences but it may be useful when you are de-activating users who no longer work for your company. There are three options for purging user preferences.
 
1. Declaratively Using a Page Process
With this option you can purge all current user preference entries for a particular user and APEX Application. When the below page process runs, it will purge all user preferences for the current user and APEX application. 

​In the page process above, we again have Identification > Type set to ‘User Preferences’. This time, we have the Settings > Type set to ‘Reset Preferences (remove all preferences for current user)’.
 
2. Via Workspace Administration
As a workspace administrator, you can view and purge user preferences for the currently logged in user or a specified user. You can access these options using the following navigation from Workspace Administration: Manage Service > Session State > Manage Preferences

​The screen shot below (from the ‘Purge Preferences by User’ option) shows preferences for user ‘JDIXON’. Clicking ‘Purge User Preferences’ will purge all preferences for this user.

​Finally, there is an API you can call to purge a single user preference for a given user in the current application. The following code will delete the preference ‘DASHBOARD_VIEW’ for the currently logged in user in the current application.

Without User Preferences, you would have to build a table and PL/SQL package to manage this kind of data in your APEX applications. The fact that this feature is baked into APEX saves you time and lets you focus on value-add features of your Application.
 
Here is the link to the APEX 19.1 documentation on user preferences:

​Full disclosure, I have absolutely no experience in trying to convince my boss to try APEX or ORDS. I do, however, have experience in basking in the glow of clients who have reaped the benefits of implementing mission critical systems using these two no-cost options of the Oracle database.
 
TL;DR; If you are a boss, try out APEX and ORDS today. If you already have an Oracle database, it costs you nothing extra and the upsides for you and your business are tremendous.

​If you are a developer looking to convince your boss to adopt APEX and ORDS, then this post is for you. My goal is to arm you with the material you need to make a compelling case for adopting APEX and ORDS. I have broken the post into several major talking points. At the start of each talking point, I have a headline statement (for bosses with short attention spans). I then go on to explain my reasoning in a little more detail (for bosses that need some evidence).

​Data Centric - APEX, because of its architecture, is very data centric. Both the code and the data exist in the same database enabling zero data access latency. This architecture did no come about by accident; there are good reasons why your code should be right next to your data. I have been using APEX for a while now, but I love this new term ‘zero data latency’. Of course, this has been true since the days of HTMLDB. But in this world of super complex, mega frameworks that are so abstracted from the data they need a map to find it, it is very relevant today.
 
Stateless – Much of the scalability of APEX comes from its stateless nature. The API calls to the Oracle APEX engine use the standard Oracle database connection pool. This means that once an API call is processed and the response is sent back to the browser, the connection is returned to the database connection pool and can be used by any other request. The database sessions are only active when performing a request, otherwise, the they are inactive and do not consume any database resources. This allows APEX to handle tens of thousands of users simultaneously.

APEX is very stable, easy to upgrade and new features are coming thick and fast.
 
You may think stability and innovation don’t belong in the same sentence. When you are talking about APEX, however, they really do. I have never undertaken a large JavaScript framework project. I can imagine, however, that as a boss it is a little un-nerving heading into a multi-year project with half a dozen technologies, many of which may not exist by the time the project is over. APEX has been around for 15+ years and there is no sign of it going anywhere. You may think, “So what, Windows has been around for longer and it is still awful.”. APEX is different. The pace of new (and useful) features over the past 2-3 years (especially in the areas of UI, Single Sign On and integration capabilities) has been fantastic. BTW, there is no sign of that pace letting up. With multiple releases a year you get the option of up taking these improvements at regular intervals.
 
Hold on a minute, that doesn’t sound very stable. What I haven’t mentioned is that the APEX development team is world famous for providing upgrades that do not break your existing Apps. One of the ways they achieve this is by allowing apps to run in previous versions with ‘Compatibility Mode’. This means that in most cases, you can do the upgrade and then switch on new functionality in individual apps, as and when you need it. There are stories every month of APEX users who have upgraded from APEX 3 (released in 2007) to the current version without anything breaking. Can you imagine doing that with any other development framework?

Your users will love using APEX Applications!
 
If you had experience of APEX from version 4 (or before), boy are you in for a treat. Applications built with APEX look as good as any other framework and are quite frankly a joy to use. We are long past the dystopian days of automaton workers using systems they are forced to use. When people use Enterprise systems these days they expect more. While you may feel like dark mode is a fad, Apple is about to release it across all of the Operating Systems. Believe me, your Enterprise users will be using dark mode soon enough. Wouldn’t it be great if your development platform could make dark mode happen at the flick of a switch? APEX has your back. Dark mode is already available in APEX Builder and will be coming soon as an end user theme style. It goes much further than that too. APEX’s Universal Theme delivers UI components that would otherwise consume hundreds of hours of custom development. For a peak at what is available, check out the Universal Theme demo App https://apex.oracle.com/ut
 
Finally, with accessibility concerns finally being taken seriously, it is good to know that the APEX team has baked accessibility checks right into the product. They even have accessibility tested themes available. Check out this video for more details on Accessibility in APEX.

​APEX and ORDS provide you everything you need to host and consume REST based web services to meet all of your integration needs.
 
Oracle REST Data Services (ORDS) has two roles in an APEX world. One is to service APEX pages to end users and the other is to host REST based web services. The ability to host REST based web services based on SQL and PL/SQL is extremely powerful. It allows you to provide external systems secure access to the data in your Oracle database. This can be useful for integrations and even for hosting web services to be consumed by native mobile applications. See our post on ORDS for details.
 
APEX comes with a number of features to facilitate consumption of any REST based web services. For example, Web Source Modules provide a wizard-based approach to configuring components that allow you to create reports and forms directly on web services. This extends the reach of APEX outside the database and prevents un-necessary syncing of data to and from other systems. 

With APEX Social Sign-In you can use just about any OAuth identity provider to authenticate your users.

Authentication can be a complex proposition. If you store usernames and passwords yourself you really need to know what you are doing. The last thing you want is for your user account data to be compromised. It is generally far safer to outsource this task to a trustworthy identity provider such as Okta or Auth0. You could also outsource this task to platforms your users already use such as Office 365, Google and even Facebook. 

​By providing the ability to create custom authentication schemes, APEX has always provided flexibility in authenticating users. Custom authentication schemes allow you to create code that could use just about anything to authenticate a user. Since APEX Social Sign-In was introduced in APEX 18.1, APEX authentication has reached a whole new level. You can now setup declarative authorization schemes for OAuth-capable identity providers and APEX handles calling the necessary web services to authenticate your user. Taking Okta for example. Okta can now be your source of truth for handling all authentication in your company. All of your other systems (Email, ERP and your APEX Apps) can then use Okta to authenticate your users. See our post on APEX Social Sign-In for more details.

​APEX provides many useful features and utilities out of the box, that would otherwise require numerous third-party libraries.
 
To name a few:

• Out of the Box Authorization
• Multi-Language and globalization features
• Sending Emails
• Email Templates
• Extensible plugin framework with hundreds of available plugins
• Building and parsing JSON
• Excel and CSV parsing
• Zipping and Unzipping files
• JWT Handling
• String manipulation utilities
• and many more…

 
The benefit of having these utilities bundled with APEX are that fixes and enhancements are handled by Oracle and released with each new version of APEX. In contrast, having these types of utilities spread out amongst a number of providers means you get fixes when they feel like. It also means that as those providers drop by the wayside you are left having to merge new libraries into your applications.

​APEX applications can be hosted in the cloud just as easily as on-premise.
 
The APEX architecture lends itself well to running in the cloud and there are numerous options for hosting APEX in the cloud.
 
PaaS - There are turn key PaaS solutions (e.g. Exadata Express from Oracle) that host the entire APEX and ORDS architecture at a very reasonable price. All you need is a credit card and a browser to get started. See our post on using APEX to extend Oracle ERP Cloud.
 
IaaS - You can also install APEX and ORDS yourself on infrastructure from just about any cloud provider. This allows you complete flexibility to size the environment as you wish, but you will need to perform much of the maintenance (backups, upgrades etc.) yourself.

​APEX is building on its high productivity heritage to establish itself as a legitimate contender in the Low Code space.
 
APEX has always been known for allowing developers to build useful, scalable applications in a very short period of time. Over the past year and a half, more and more features have been added to establish APEX as a top contender in the low code pace. These features include wizard-based development of web service integrations and pre-built components that can be added to existing applications or used to build brand new applications. APEX is already at the stage where you can build fully functional applications starting from the upload of an Excel spreadsheet. These kinds of features are allowing APEX to break out of the IT department and into the business. It is here where (handled the right way), citizen developers can become productive with APEX with just a small amount of oversight from IT. 

​Many of our customers run Oracle e-Business Suite and have a number of PL/SQL developers on staff. How to leverage this talent and still provide your users with applications they will love using? An experienced PL/SQL developer can be up and running on APEX in a matter of days. Five years of Oracle database, SQL and PL/SQL experience gives you about 70% of the skills to be a high performing APEX developer. Sprinkle in a little JavaScript, CSS and web services experience and you are 100% of the way there.

​APEX and ORDS are no cost options of the Oracle Database.  If you own an Oracle database license you own APEX and ORDS.
 
I purposely left this item to last because in my opinion, APEX and ORDS stand on their own against any enterprise-ready development platform. Having said that, if you own an Oracle database license you really should be using APEX and ORDS because it isn’t going to cost you a penny extra. In addition to the no extra cost for the software, you will also need very little additional hardware.  A VM with 4GB of RAM and 15GB disk is more than enough to host ORDS, which is the only other component you need.

It’s very hard to write a pithy conclusion to summarize everything I have said in this post. There are also, no doubt, a number of important APEX benefits that I have not included. If you read this post and you are a developer keen to bring APEX and ORDS into your organization, I encourage you to use some of this material to make a case. If you are a boss and you are looking to adopt a development platform that will deliver real value to your business, then I urge you to visit the following links to learn more about what APEX and ORDS can offer your organization:

• APEX Shortcuts
• APEX Office Hour Videos
• APEX Learning

​Oracle REST Data Services (ORDS) provides many options for authenticating users. These include OAuth client, APEX User, Database Schema User and OS User. While it is important to ensure your ORDS web services are secured, you also need to consider what a client has access to once authenticated. As a quick reminder, authentication confirms your identity and allows you into the system, authorization decides what you can do once you are in. In this post, I will dive into roles and privileges and explain their part in authorizing access to ORDS web services for OAuth clients.

​Let’s start with a diagram to show how roles and privileges fit into the overall OAuth security model for ORDS.

A role acts as the link between one or more users and one or more privileges. You assign a role to one or more OAuth clients.
 
A privilege details what is secured by that privilege. When creating a privilege, you can secure either an entire module or secure based on URL patterns.
 
A URL pattern is part of the full URL for a web service or group of web services. If you have a module called ‘ev’ then you can secure all services in that module using the URL pattern ‘/ev/*’.

Take the following three modules in an ORDS enabled schema called ‘XXORDS’.

Let's say we want to do achieve the following:

• Allow services in the twillio module to be completely open (i.e. no authentication)
• Protect the 'utils' and 'ev' modules
• Allow the OAuth client ‘ADMIN_CLIENT’ access to any services in the 'utils' and 'ev' modules
• Allow the OAuth client ‘EV_CLIENT’ access to services in the 'ev' module

 
Note: Prior to creating any privileges, all of your ORDS web services will be publicly accessible.
 
Roles
Based on the above, we will need to create two roles ‘ADMIN_ROLE’ and ‘EV_USER_ROLE’.

We will also need to create two privileges. One to protect web services in the ‘ev’ module and one to protect web services in the ‘utils’ module.

Privilege 1 - EV_DATA_ACCESS
While creating this privilege, we will at the same time, link the privilege to both the 'EV_USER_ROLE' and the 'ADMIN_ROLE' roles. An OAuth client associated with either of these roles will be able to call the charge points web service:

• https://example.com/ords/xxords/ev/charge_points

​Note: The pattern ‘/ev/*’ starts after the base URL for your ORDS enabled schema. In our case, this is anything after https://example.com/ords/xxords.
 
This is what the privilege looks like from SQL Developer:

Privilege 2 - UTILS_DATA_ACCESS
While creating this privilege, we will only link the privilege to the 'ADMIN_ROLE' role. Only OAuth clients associated with this role will be able to call the 'dbinfo' web service:

• https://example.com/ords/xxords/utils/dbinfo

​If we stopped here, then there would be no way to access any web services in the ‘ev’ or ‘utils’ modules. The act of associating a privilege with a module or URL pattern effectively locks them down. We need to create OAuth clients and link them to the roles we created so that these clients can access web services in these modules.

OAuth Client 1 - EV_CLIENT
This script creates the OAuth client EV_CLIENT using the grant type ‘client_credentials’. It then grants the newly created client access to the EV_USER_ROLE. At this point the EV_CLIENT can call web services in the ‘ev’ module.

​OAuth Client 2 - ADMIN_CLIENT
This script creates the OAuth client ADMIN_CLIENT using the grant type ‘client_credentials’. It then grants the newly created client access to both the EV_USER_ROLE and the ADMIN_ROLE. At this point the ADMIN_CLIENT can call web services in the ‘ev’ and ‘utils’ modules.

In this post, I demonstrated how to use roles and privileges to provide fine grained access to your ORDS web services. ​​This is important when ensuring OAuth clients only have access to the web services they are supposed to. Unless your web service has to be public (e.g. if it is a Web-hook) then you should seriously consider adding OAuth security. 

Click here for more on OAuth security in ORDS.