Creating a Google XML Sitemap using Oracle APEX. #JoelKallmanDay

Oracle APEX makes it easy to build modern web apps, but ensuring that your public pages are properly indexed by Google sometimes requires a little extra work. Recently, I was asked to generate a dynamic XML Sitemap for one such APEX app, and here’s how I went about it.

What is a Google Sitemap, and why is it important?

A Google Sitemap is a simple XML file, usually named sitemap.xml, that lists all the important URLs on your site along with metadata like update dates and priority. It helps search engines like Google discover and understand the structure of your site more efficiently, especially pages that may be hard to find via internal links or other navigation. Submitting it through Google Search Console gives you visibility. In short, it is a practical means to ensure faster, more reliable indexing of your site.

Our APEX application

For simplicity, we’ll ignore the non-essential parts and reduce the app to its three main pages.  The pages that we want to appear on the Google XML Sitemap are the detail pages. We want to be sure that each one of our thousands of articles are indexed.

• A home page
• A search page
• A detailed page for each entry in the database (1,000s of entries)

Understanding the XML structure

The first step was to check Google’s documentation for the required XML structure:

Google Sitemap XML documentation

<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
  <url>
    <loc>https://www.example.com/foo.html</loc>
    <lastmod>2022-06-04</lastmod>
  </url>
</urlset>

We quickly realized that, for our use-case, we also needed to include a News Sitemap:

Google News Sitemap documentation

<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"
    xmlns:news="http://www.google.com/schemas/sitemap-news/0.9">
  <url>
    <loc>http://www.mysite.org/ords/r/press/articles?p_slug=companies-a-b-in-merger-talks</loc>
    <lastmod>2022-06-04</lastmod>
    <news:news>
      <news:publication>
        <news:name>The Example Times</news:name>
        <news:language>en</news:language>
      </news:publication>
      <news:publication_date>2008-12-23</news:publication_date>
      <news:title>Companies A, B in Merger Talks</news:title>
    </news:news>
  </url>
</urlset>

Our Data Source: vw_articles View

For the purposes of this blog, I’ve replaced the actual view that we used with a view called vw_articles containing generated demo data. The view returns a list of news articles along with metadata such as their unique IDs, titles, publication dates, last update dates, etc.  A field called url_slug contains a descriptive but also unique, alternate key in a readable text form (e.g., tree-falls-in-a-forest, prime-minister-slips-on-banana) 

Name             Null?    Type          
---------------- -------- ------------- 
ARTICLE_ID       NOT NULL NUMBER        
TITLE            NOT NULL VARCHAR2(200) 
URL_SLUG         NOT NULL VARCHAR2(200) 
PUBLICATION_DATE NOT NULL DATE          
LAST_MODIFIED    NOT NULL DATE          
AUTHOR                    VARCHAR2(100) 
CATEGORY                  VARCHAR2(50)

Generating the XML per article

Now that we know what XML structure Google expects, let’s generate it dynamically using SQL. We'll start by generating the XML for each article. This will generate one row for each article. Each row will contain the XML describing that article.

select xmlelement("url",
         xmlelement("loc", 'http://www.mysite.org/ords/r/press/articles?p_slug=' 
                           || a.url_slug),
         xmlelement("lastmod", to_char(a.last_modified, 'YYYY-MM-DD')),
         xmlelement("changefreq", 
                     case
                       when a.last_modified > sysdate-15 
                         then 'daily'
                       when a.last_modified > sysdate-60 
                         then 'weekly'
                         else 'monthly'
                     end),
         xmlelement("priority", 
                     case
                       when a.last_modified > sysdate-15 
                         then '0.8'
                       when a.last_modified > sysdate-60 
                         then '0.6'
                         else '0.4'
                     end),
          xmlelement("news:news",
            xmlelement("news:publication",
              xmlelement("news:name",'The Best Daily News '||a.article_id),
              xmlelement("news:language",'en')
             ),  
            xmlelement("news:publication_date", a.publication_date),
            xmlelement("news:title", a.title)
           )
         )
  from vw_articles a;

You may notice that we’ve set each entry’s change frequency (changefreq) and priority dynamically - they are set based on the number of days since the article was last updated.

The SQL statement above gives us something that looks like this for each entry:

<url>
 <loc>http://www.mysite.org/ords/r/press/articles?p_slug=olympic-athletes-break-three-world-records</loc>
 <lastmod>2025-05-18</lastmod>
 <changefreq>monthly</changefreq>
 <priority>0.4</priority>
 <news:news>
  <news:publication>
   <news:name>The Best Daily News 4</news:name>
   <news:language>en</news:language>
  </news:publication>
  <news:publication_date>2025-05-18</news:publication_date>
  <news:title>Olympic Athletes Break Three World Records</news:title>
 </news:news>
</url>

Aggregating entries into a sitemap

Rather than generating multiple XML fragments, we’d like to aggregate each entry into a single XML document. To do this, we first use the XMLAGG function so that all the entries are returned as a single, aggregated row. We would like the entries to be sorted in descending order by last_modified, so we add order by a.last_modified desc to the end of the XMLAGG function.

We’ll enclose these aggregated entries inside a <urlset> tag to create a complete, valid XML document. Finally, we’ll use xmlserialize to convert our XMLTYPE output to an indented CLOB. We’ve also added the XML declaration at the start of the document.

select '<?xml version="1.0" encoding="UTF-8"?>' || chr(10) ||
   xmlserialize(
     content
     xmlelement(
           "urlset", 
           xmlattributes
              ('http://www.sitemaps.org/schemas/sitemap/0.9' as "xmlns",
               'http://www.google.com/schemas/sitemap-news/0.9' as "xmlns:news"),
           xmlagg(
             xmlelement("url",
               xmlelement("loc", 'http://www.mysite.org/ords/r/press/articles?p_slug=' 
                                 || a.url_slug),
               xmlelement("lastmod", to_char(a.last_modified, 'YYYY-MM-DD')),
               xmlelement("changefreq", 
                          case
                            when a.last_modified > sysdate-15 
                              then 'daily'
                            when a.last_modified > sysdate-90 
                              then 'weekly'
                              else 'monthly'
                          end),
               xmlelement("priority", 
                          case
                            when a.last_modified > sysdate-15 
                              then '0.8'
                            when a.last_modified > sysdate-90 
                              then '0.6'
                              else '0.4'
                          end),
                xmlelement("news:news",
                  xmlelement("news:publication",
                    xmlelement("news:name",'The Very Best Daily News'),
                    xmlelement("news:language",'en')
                   ),  
                  xmlelement("news:publication_date", a.publication_date),
                  xmlelement("news:title", a.title)
                 )
               )
            )
        )
     as clob indent size = 2
   ) as xml_output
from vw_articles a;

 For very large datasets (tens of thousands of URLs), consider chunking your sitemap into multiple sitemap files and generating a sitemap index file, as per Google’s recommendation (maximum 50,000 URLs per sitemap).

Final XML

This gives us our final XML, which is one <urlset> that encompasses all the <url> entries that we want to appear on the sitemap:

<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9" xmlns:news="http://www.google.com/schemas/sitemap-news/0.9">
  <url>
    <loc>http://www.mysite.org/ords/r/press/articles?p_slug=climate-change-policy-update</loc>
    <lastmod>2025-08-17</lastmod>
    <changefreq>daily</changefreq>
    <priority>0.8</priority>
    <news:news>
      <news:publication>
        <news:name>The Very Best Daily News</news:name>
        <news:language>en</news:language>
      </news:publication>
      <news:publication_date>2025-08-16</news:publication_date>
      <news:title>Climate Change Policy Update</news:title>
    </news:news>
  </url>
  ...
  ...  thousands of entries
  ...
</urlset>

You can validate your sitemap using the W3C XML Validator or Google’s own testing tools before submitting.

Serving the Sitemap from APEX

1. Create a blank APEX page with a minimal template. Call this new page sitemap with an alias of sitemap. Make sure that this page is a public page.

2. I strongly recommend using packages when developing any substantial piece of PL/SQL. For this example, I’ve created a package that contains the SQL statement to generate the XML shown above. The package is called googlesitemaps and you can download it from here.
   
   Basically, this package's procedure generateMainSitemap selects the XML <urlset> into a CLOB and then outputs that CLOB to the HTTP stream.

   procedure generateMainSitemap is
      l_clob_output  clob;  -- Holds the generated XML sitemap content
   begin
     ...
     ...   (removed for brevity)
     ...   A section that retrieves the XML in a CLOB variable 
     ...   called l_clob_output using the SQL shown earlier.
     ...   You can download this using the link above
     ...
     
     -- Set HTTP response content type to XML
     owa_util.mime_header('application/xml', false);
     
     -- Specify content length for client optimization
     htp.p('Content-Length: ' || dbms_lob.getlength(l_clob_output));
     
     -- Close HTTP headers
     owa_util.http_header_close;
     
     -- Output the XML content without HTML escaping (preserve XML structure)
     apex_util.prn(p_clob => l_clob_output, p_escape => false);

   end generateMainSitemap;

3. Once the package is in place, create a pre-rendering, before-header process called “Output the XML sitemap”. Inside the begin ... end, this process will contain two lines.
   
   The first one calls the googlesitemaps.generateMainSitemap procedure to output the XML directly to the HTTP stream.
   
   The second one calls apex_application.stop_apex_engine to stop all APEX processing dead in its tracks. This ensures that nothing else is output to the HTTP stream.

Submitting the sitemap to the Google Search Console

Now we're ready to submit the sitemap to Google.  
Google will automatically search for a file called "sitemap.xml" but, unfortunately, with the current version of APEX (24.2), we can't add a dot in a page alias.  This means that we can't "pretend" to have a file called "sitemap.xml".  

The workaround to this is to submit your new sitemap directly to Google using the Google Search Console for your site.  The search console looks something like this.

If we click on Sitemaps we’ll come to a page that looks like this:

Here, you simply have to enter the URL of your newly created sitemap page and submit it to Google. It won't be processed immediately, but it will be added to a queue for processing. In my experience, it seems to get processed within two or three days.

Conclusion

So, there we have it. With this approach, you can make your APEX applications more discoverable and ensure your content reaches a wider audience through proper search indexing.  I hope that this blog post helps some of you make your public-facing APEX applications gain a wider audience.

Happy APEXing!!

Oracle APEX: How Application and Page Processes really execute at the same process point

Debugging a legacy application recently gave us a deeper understanding of the order in which Oracle Application Express executes Application Processes and Page Processes when they share the same process point.

In our case, the point of interest was "Before Header".

When discussing this with a few other developers, some believed the order was:

1. First: Application processes – in sequence number order within the list of "Before Header" application processes

2. Then: Page processes – in sequence number order within the list of "Before Header" page processes

Most of us (myself included) had never really checked — and weren't entirely sure.

To confirm, I created a simple, single-page test application with 5 processes. Each process wrote a message to a table called logtable.

1. Application processes ("On Load: Before Header"):

   • test05 (sequence 5)

   • test15 (sequence 15)

   • test25 (sequence 25)

2. Page processes ("Pre-rendering – Before Header"):

   • test10 (sequence 10)

   • test20 (sequence 20)

3. Added a simple Classic Report to display logtable's contents ordered by execution sequence.

Here's a screenshot of the application processes:

And here are the page processes:

Page Process - Before header: sequence 10

Page Process - Before header: sequence 20

The output was unambiguous:

Application and page processes are executed together in strict sequence number order. They are interleaved.

What does this mean for us as Oracle APEX developers?

If your Oracle APEX application has both application and page processes at the same process point, the sequence number alone determines execution order - not whether it's an application or page process.

A practical tip:

If you want all page processes to run *after* all application processes, give them higher starting sequence numbers (e.g., 1010, 1020, …).

Happy APEXing!!

Using PL/SQL to Seed and Publish Oracle APEX application translations

For multilingual applications, it can become a little tiresome to constantly have to reseed and republish your application while testing multiple languages or debugging language-switch problems.

The other day, while tracking down a tricky language-switch bug, I thought to myself that there must be a faster way to seed and publish.  So I pulled up the documentation for the APEX_LANG API and found these two procedures: apex_lang.seed_translations and apex_lang.publish_application.

Using these two procedures meant that I could write a little script to seed and publish my application (ID 12345) in French and Spanish:

begin
  apex_lang.seed_translations   
     (p_application_id => 12345, p_language => 'fr');
  apex_lang.publish_application 
     (p_application_id => 12345, p_language => 'fr');

  apex_lang.seed_translations
     (p_application_id => 12345, p_language => 'es');
  apex_lang.publish_application 
     (p_application_id => 12345, p_language => 'es');
end;

Note, however, that when running the above outside an APEX environment, this script fails to execute. This because the security group for this workspace needs to be manually set. The error message looks like this:

ORA-20001: Package variable g_security_group_id must be set.
ORA-06512: at "APEX_240200.WWV_FLOW_IMP", line 109
ORA-06512: at "APEX_240200.HTMLDB_LANG", line 328

To set the security group for the workspace, we first have to retrieve the workspace ID and then call the apex_util.set_security_group_id procedure. An additional complication is that a schema may be associated with more than one APEX workspace, but we'll deal with that shortly.

declare
  l_workspace_id  apex_workspaces.workspace_id%type;
begin
  -- get the workspace ID for this schema 
  -- (for now, let's assume there's only 1) 
  select workspace_id 
    into l_workspace_id
    from apex_workspaces;  
  --
  -- set security group for the Oracle APEX workspace 
  apex_util.set_security_group_id (l_workspace_id);
  
  -- seed and publish french
  apex_lang.seed_translations   
     (p_application_id => 12345, p_language => 'fr');
  apex_lang.publish_application 
     (p_application_id => 12345, p_language => 'fr');

  -- seed and publish spanish
  apex_lang.seed_translations
     (p_application_id => 12345, p_language => 'es');
  apex_lang.publish_application 
     (p_application_id => 12345, p_language => 'es');
end;

Well, that takes care of my immediate issue for application 12345 and the French and Spanish translations.  

But.... Wouldn't it be so much better if we could have a solution that would check whether any of my applications need seeding and publishing, and that would then seed and publish them as needed?

We can start building one by querying the APEX data dictionary view apex_application_trans_map.  The requires_synchronization column tells us which language translations need to be seeded and published. This query returns results for all of the potential multiple APEX workspaces associated with the current schema. So it handles the multiple workspace issue alluded to earlier in this blog post.

select t.*
  from apex_application_trans_map t
 where substr(t.requires_synchronization,1,1) = 'Y'
 order by t.primary_application_id,
          t.translated_app_language;

We've got pretty much everything that we need to put it all of this together as a procedure:

1. Let's loop through an SQL query that retrieves every language translation (translated_app_language) that needs to be synchronized for this schema along with its workspace, application name and ID.

2. Within the loop, whenever there's a change of workspace, we'll reset the security group.

3. We'll then seed and publish the application translation.

4. The procedure will accept a single parameter, p_app_id.  If this parameter is passed with a value of null, it will loop through, seed and publish all APEX applications that need to be synchronized.  This will be done across all the APEX workspaces associated with the current schema.

procedure seedAndPublishTranslationsApp (
  p_app_id in apex_application_trans_map.primary_application_id%type
) is
  l_workspace_id apex_workspaces.workspace_id%type := 0;
begin
  --
  -- Loop through all of this schema's workspaces that have applications
  -- with translation languages that require synchronisation.
  --
  for rec_trans in (
    select t.workspace,
           t.primary_application_name,
           t.primary_application_id,
           t.translated_app_language,
           w.workspace_id
      from apex_application_trans_map t
           join apex_workspaces w
             on w.workspace = t.workspace  -- to get workspace ID
     where t.primary_application_id = nvl(p_app_id, t.primary_application_id) -- null means all apps
       and substr(t.requires_synchronization, 1, 1) = 'Y'
     order by w.workspace_id,
              t.primary_application_id,
              t.translated_app_language
  ) loop
  
    -- If there's a change of workspace, (re)set the security group.
    if l_workspace_id <> rec_trans.workspace_id then
      dbms_output.put_line('Workspace: "' || rec_trans.workspace || '":');
      apex_util.set_security_group_id(rec_trans.workspace_id);
      l_workspace_id := rec_trans.workspace_id;
    end if;

    apex_lang.seed_translations(
      p_application_id => rec_trans.primary_application_id,
      p_language       => rec_trans.translated_app_language
    );

    apex_lang.publish_application(
      p_application_id => rec_trans.primary_application_id,
      p_language       => rec_trans.translated_app_language
    );

    dbms_output.put_line(
      'Seeded and published language: "' || rec_trans.translated_app_language ||
      '" for application: ' || rec_trans.primary_application_id || ' - ' ||
      rec_trans.primary_application_name
    );
  end loop;

end seedAndPublishTranslationsApp;

As I don't particularly like having free-floating procedures and functions cluttering up my database, I've made a package, translateTools, that encapsulates this procedure.  You can download the package here.

There are various ways that you can use this procedure.
For example, during development, I like to have a worksheet open that let's me quickly run
  exec translateTools.seedAndPublishTranslationsApp();
whenever I want to. It certainly saves me a lot of clicking within the APEX application development environment.

Another use-case could be to implement it as a regular job that will run nightly to ensure that there are no unpublished translations left lying around.

It's a small solution to a small problem. I hope that some of you will find it useful.

Happy APEXing and Happy Translating!!