ORDS Java heap space OutOfMemoryError

I recently ran into a problem with an Apex application running on ORDS on Tomcat. The application has a page with a custom tabular form (built using the apex_item package). When this page is submitted, the form values are stored in the "g_fxx" arrays (g_f01, g_f02, etc).

The problem was that when the number rows (and therefore the number of elements in the arrays) got too big, the server would respond with a HTTP 500 (more...)

APEX Reports : Double click to edit

Apart from the Current Record Indicator in your APEX Reports, another question often pops up at my client sites. A lot of functionality is implemented using a Report and a (Modal) Form. But to access that Form, the user has to click exactly on the small link icon in the first column of the report. So can that be changed, making it more "accessible"?

Set the Link Attributes of the column you're using for (more...)

Implementing a Current Record Indicator in your APEX Reports

Developers with an Oracle Forms background might still remember this nice feature: If you click on a row in an Oracle Form "report" then it can be highlighted - either the full row or just a small first item of the row. The main difference with the Oracle Forms "reports" and the APEX Reports is that in Forms a "report" is usually comparable to an APEX Tabular Form. But a similar feature is frequently asked (more...)

Sometimes it works, sometimes it doesn’t …

Recently at a client site I ran into a strange issue. There was an APEX page where you can set some parameters and then a report would refresh according these new settings. But the strange thing was: Sometimes it worked perfectly, but sometimes it didn't. In the latter case one or more of the parameters seem discarded... WTF ??

So I dived into it and looked at the code. The parameter / refresh mechanism was implemented (more...)

My nominations for the Oracle Database Developer Choice Awards 2015


I'm honored to have been nominated for the Oracle Database Developer Choice Awards 2015, in no less than three (!) categories: PL/SQL, Application Express (Apex) and Oracle REST Data Services (ORDS).


Here's a short video that explains what the Oracle Database Developer Choice Awards are all about:

If you are a regular reader of my blog, you are probably familiar with my contributions to the Oracle Database Developer community, but here is (more...)

About using APEX_COLLECTIONS in a tabular form with INSTEAD OF triggers

Always check out the original article at http://www.oraclequirks.com for latest comments, fixes and updates.   In case you dreamed of updating an Apex tabular form built on top of a view based on APEX_COLLECTIONS by means of INSTEAD OF triggers, you must be ready to grant the following rights to the schema user attached to the workspace, otherwise you'll get an ORA-01031: Insufficient privileges

Installing Oracle XE, ORDS and Apex on CentOS – Part Four: Stress testing

This is part four in a series of blog posts about how to install Oracle 11g Express Edition (XE) with Oracle Application Express (Apex) on a CentOS Linux server, with Apex served by Oracle REST Data Services (ORDS) running on top of Tomcat and Apache.

After setting up a small CentOS server with Oracle Express Edition (XE), I wanted to stress test it to see how much load such a barebones installation can handle. In (more...)

Installing Oracle XE, ORDS and Apex on CentOS – Part Three: Additional configuration

This is part three in a series of blog posts about how to install Oracle 11g Express Edition (XE) with Oracle Application Express (Apex) on a CentOS Linux server, with Apex served by Oracle REST Data Services (ORDS) running on top of Tomcat and Apache.

By now, you should have a working installation of CentoOS with Oracle XE, Apex, ORDS, TomCat and Apache. There are still some additional configuration and optimization we should do, which (more...)

Installing Oracle XE, ORDS and Apex on CentOS – Part Two: Installation

This is part two in a series of blog posts about how to install Oracle 11g Express Edition (XE) with Oracle Application Express (Apex) on a CentOS Linux server, with Apex served by Oracle REST Data Services (ORDS) running on top of Tomcat and Apache.

Let's get right to it, starting with Oracle XE.

Installing Oracle XE

This is actually quite straightforward, assuming you have followed the prerequisite steps in part one.



As part of (more...)

APEX 5: forgot the images?

On my play environment I usually use Oracle APEX with the Embedded PL/SQL Gateway, just because it's so easy.
When a new version of APEX is released, just like everybody else, I upgrade my play environment.
After the apexins.sql script is run, I always want to start playing with it immediately. Usually it is at this point where I just see a blank page... scratching my head wondering why it is not running,... having (more...)

Oracle Application Express (APEX) 5.0 available for download

The best Oracle Application Express edition of all times has finally landed. Info & details in Apex's official blog. Enjoy.

APEX: Active Tabs Based on Page Groups

Recently someone asked me: "How did you do that? When I include an APEX page in a Page Group, the correct tab is automatically highlighted"
When I setup an application, I usually use Dimitri Gielis' method, so instead of using "real tabs", I use a List and display that list as Tabs.
For each of the "Tabs", I also create Page Groups, just to keep things organized.
Each of the List Entries will have a (more...)

Deploying Application Express with Delphix

VDBs

Seamless cloning of an application stack is an outstanding goal. Seamless cloning of an application stack including the full production database, application server, and webserver in a few minutes with next to zero disk space used or configuration required is the best goal since Alexander Graham Bell decided he wanted a better way tell Mr. Watson to “come here.”

So in the spirit of discovery, I’ve installed Oracle REST Data Services (ORDS) 2.0 (more...)

Apex multilingual applications and build options

Always check out the original article at http://www.oraclequirks.com for latest comments, fixes and updates. Just a quick reminder for those who are devoloping Apex multilingual applications: Build options' state is propagated to translated applications at the time of seeding, so you need to be careful when changing the state of a build option in the primary language because you may end up

UKOUG Tech14 – APEX Highlights




Last week I spent 4 days at the annual UK Oracle User Group conference, this time around called Tech14.  It was my first UKOUG conference in a number of years and I set out with the intention of treating it like an all you can eat buffet of APEX presentations and workshops.

So, what were the APEX highlights of Tech14? Well, I have to start with the presentations given by Joel KalmanDavid Peake (more...)

Can you build business critical applications with APEX?

Now and then this question pops up. And today this question was delivered to my mailbox again. A customer is busy starting a project to replace a current Oracle Forms application. So he asked Oracle and one of the Oracle partners: What should we use, APEX or ADF? A valid question that has been asked - and will be asked - by numerous customers. 
Of course, there is only one correct answer and that (more...)

ORA-20104: create_collection_from_query ParseErr:ORA-00918: column ambiguously defined

Always check out the original article at http://www.oraclequirks.com for latest comments, fixes and updates.   If you are wondering why you are getting this error message after following the example in the documentation describing procedure CREATE_COLLECTION_FROM_QUERYB2 in the APEX_COLLECTION API, the quick answer is that the sample code is flawed. ORA-20104: create_collection_from_queryb2

Apex substitution strings in reports, not always replaced with their values, guess why?

Always check out the original article at http://www.oraclequirks.com for latest comments, fixes and updates. It's amazing to you find out how easy is to take for granted certain features of Apex for the simple fact that you have been using them for a long time without paying too much attention to certain specific details. This morning I ran a report that I rarely use in an application and to

How many page views can Apex sustain when running on Oracle XE?

Always check out the original article at http://www.oraclequirks.com for latest comments, fixes and updates. While some people think that hosting a web site on top of Oracle XE can be hardly considered much more than a joke, I can claim instead, basing on my personal experience of the last 5 years, that for small sites it can be a perfectly reasonable choice, provided you have the technical

Time for an Oracle Apex feature request – single sign-on authentication

I've just submitted a feature request because I believe that the current Application Group concept is a fairly weak one if it doesn't bring about some advantage in terms of features for the developer. Basically what I am asking for is that one can easily implement a single sign-on authentication method across multiple applications within the same application group, pretty much like the existing