Thursday, 3 March 2016

Identify Fire on Page Load DA Actions

Today I am investigating performance problems on an Oracle Apex page. On of the possible causes are JavaScript DA Actions that are Fired on page load. The following query helps to identify these DA Actions:

select distinct da.page_id
     , da.page_name
     , da.when_event_name
     , case when when_selection_type is not null then 
                    when_selection_type ||':' || when_element || when_region
            else null
       end    as  object_name
     , da.dynamic_action_name
from   apex_application_page_da_acts   act
       join apex_application_page_da   da  on ( da.dynamic_action_id = act.dynamic_action_id ) 
where  act.action_code = 'NATIVE_JAVASCRIPT_CODE'
  and  act.application_name = '[app_name]'
  and  act.page_id = [page_id]
  and  substr(act.execute_on_page_init,1,1) = 'Y'

Fill in the name of your application ([appname]) and the ID of the page ([page_id]) and run the query. You will get a list of the relevant DA Actions that you can check.

By the way, if you are at this point you could also run the query for the DA Fire on Page Load settings and contribute the survey. Happy Apexing, Dick Dral

Tuesday, 1 March 2016

Let’s wreck the default Fire on page load option

Do you recognize the situation that you have coded a nice JavaScript Dynamic Action to respond on user input, you run the page and you notice unwanted behaviour when loading the page?
Oh no, forgot to uncheck the Fire on page load option! It happens to me all the time!

In Oracle Apex JavaScript DA steps have the option Fire on page load checked by default, as you will all be aware. PL/SQL steps have it default unchecked.
I stumble regularly over forgetting to uncheck the option. Most of the DA’s I write are about responding on user actions so I normally do not want them to execute on page load. Not unchecking the option results in unwanted behaviour which is not always obvious. One time it has cost me a few hours to come to the conclusion I should uncheck it.

I would like to have the option default unchecked. This ranks high on my Apex enhancement requests list.

To back this I decided to examine how many Javascript DA steps still have the Fire on page load option active in the application I currently work on together with 5 other developers.
This is the result:

Execute on Page LoadNumber

The ratio between unchecked and checked is 2,7! A good argument for me to have the option default unchecked.

What about the Apex builder? A query on the Apex repository for application ID’s between 4000 and 5000 results in :

Execute on Page LoadNumber

Also in their own work it would be an advantage to uncheck by default!

But how about your application? I am curious what the ratio is in your application.
If you fire the query below you can find out.

select execute_on_page_init, count(*)
from   apex_application_page_da_acts
where  action_code = 'NATIVE_JAVASCRIPT_CODE'
  and  application_name = 'appname
group by execute_on_page_init;

You can fill in the application name at appname or omit this line to query the whole Apex repository.

Please you post the results on If your results also show a majority for the unchecked steps I will try to convince the Apex team of unchecking the option by default for JavaScript DA steps.

#letswreckthistogether ;-).

Happy apexing,
Dick Dral