I got a little more useful information from Fabian today:
For whatever reason, even with the $PublicAccess item set to "1", Anonymous still needs at least reader or depositor access to actually write to the agent data note. I usually prefer to restrict public readers to No access with the privilege to read and write public documents, whenever possible (there is another oddity with shared fields, who don't have a GUI widget to enable public access). Reading item values works OK that way, but writing not.
Obviously (at least in certain releases) Domino doesn't do a perfect job deleting agent data notes when agents are deleted. IBM has a little tool to purge orphaned agent data notes, but TeamStudio has a better (and free) utility.
I got this by e-mail from a friendly German, named Fabian Brock.
If the WQO agent is not run as web user, there should be no problem whatsoever. If the signer of the agent has appropriate rights to the database, he/she can modify the agent data note just like any other document. However, anonymous users will generally not have the right to create or even edit documents.
The solution is the same as with conventional docs: Have your WQO agent add a $PublicAccess item set to "1", if it doesn't exist yet. Now, Anonymous is only required to have NoAccess plus the privileges to read and create public documents. Major drawback here, since SavedData is not available for public access yet, Anonymous will never be able to add this item. The agent must have been run once by a user with sufficient access rights to make the modification.
And because the agent data note is recreated every time you make a modification to your agent, this might turn out to be hard to handle. One more reason to put as much of your code as possible into libraries.
It seems (from a little testing) SavedData is not available for web-agents, which is a shame. I tested this in both Java and LotusScript, and got the same results. Next best solution, use a profile-document.
>> Demo-code (java agent), profile document
When I first read through Julians benchmark of different ways of String concatenation, I only skimmed through to the nice graph.
I read it again, and saw that he mentioned NotesSession.SavedData which I never heard of. Looked it up in the help, and got an idea (good? you decide). Wouldn't this be a great container for HTML created by WQO?
WQO that prints data from documents (e.g. menus/reports):
Create a lookup-view with a column containing @Modified.
When you run the agent,
Join(Evaluate(@Text(@DbColumn( "" : "nocache" ; ... )))) -> a string of all the dates. Compare this to a stored field in SavedData containing the @Modified from the previous run.
If the same/SavedData has "date-field", replace RT-field in DocumentContext with the saved field in SavedData, else generate HTML/store in SavedData.