Lukas wrote:
> Hi group!
>
> The MapViewer User's Guide has this to say about using MapViewer from
> PL/SQL:
> "The usage model for the SDO_MVCLIENT package is almost identical to
> that of
> MapViewer JavaBean-based API" etc etc .. "For usage and reference
> information about specific functions or procedures, see the
> description of the associated JavaBean-Based API. methods and
> interfaces in Chapter 4"
>
> If I don't misunderstand the basic concept, in a Java Web App (using
> the MapViewer Bean) you create a MapViewer object for each HTTP-user-
> session, like so:
> MapViewer mv = new MapViewer("http://my_corp.com:8888/mapviewer/
> omserver");
> ... which you would then store in the user's session object, so that
> the MapViewer Bean conveniently holds the map's state on the user's
> behalf.
>
> To do the equivalent in PL/SQL, the User's Guide suggests:
> "connect scott/tiger
> call sdo_mvclient.createmapviewerclient(
> 'http://www.mycorp.com:8888/mapviewer/omserver')
;
>
> The preceding example creates, in the current session, a unique
> MapViewer client
> handle to the MapViewer service URL"
>
> Does "current session" refer to the HTTP-user-session? While I've used
> PL/SQL before, I've not used the PL/SQL Web Toolkit. Is the session
> handling implicit here (and invisible?) or should the sdo_mvclient be
> subsequently stored in the PL/SQL equivalent of a (J2EE) HttpSession
> object?
>
> YT
>
PL/SQL Web toolkit does nothing more than generate (badly formatted)
HTML-code. Should be pushed to the web, using a Database Access
Descriptor (DAD) on the Oracle Application Server.
Having said that (there's some stuff on my blog), http sessions
are stateless: you click in your browser, connection is made
to the webserver, passed on to the database, processes, passed
back to the web server (throught the DAD), and your browser renders
the page - no more connections.
The Oracle web server has some tricks to prevent sessions to the
database being opened and closed all the time. Maybe that is meant
here?
If not - you must maintain your own state (cookies).
( doesn't the mapviewer maintain state? What happens after
htp.p(sdo_mvclient.createmapviewerclient(
'http://www.mycorp.com:8888/mapviewer/omserver'
));
???
)
--
Regards,
Frank van Bortel
Top-posting is one way to shut me up...
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