call a php function from a button

Yes you can do this, however not any normal way, since onclick and javascript are both client-side scripting, while php is server-side scripting. To do this you will need to invoke a javascript function which then invokes a php function. then the php function returns something and javascript will update whatever it returns, and this is commonly known as AJAX.

Let me know if you need to know any more.

do you mean I should use Ajax or this is the principle of ajax where the server uses javascript to update the client screen? I am not (as you probaly realized) a web man, I only know databses but I do occasional things on the web (difficult to bypass nowadays) mainyly php.
the return I expect from php is only true or false, I could even forget about it, it always works, and the app is not using important data. so how do I call a php function from a javascript then? (if I know php a bit, I almost ignore javascript, I use it with the book on my knees (not true, the js doc on my left screen).
is there a call/exec command? how to distinguish external php scripts from internal php functions? and is thre a way to stay in the same web page during execution to minimize blank screens?

forget to mention that I use php to write to mysql mainly, can js talk to mysql directly if the mysql port (def: 3306) is open to public?

this is it, provided I can understand what this XMLHttpRequest does... do I need something special on my server to respond to this?
I'll copy the code locally to re-read it (such awful colors! maybe I should give this guy a few readability courses!).
and a philosophic remark, it is really too much energy to spend to get a name displayed, someting which is done with 2 lines of sql, 2 lines of servoy, 2 lines of filemaker.
The web definitly needs a query language which is something else than a bunch of tricks and workaround, no serious or complex app can be done this way unless you spend 2 years on it, and then come up with a huge price nobody would buy.
anyway, thanks for confirming there is no easy way to do this, I'll use yr example for my own understanding, but no way I do apps using this. the web world is rather weird, wants to be transparent and user friendly like classic apps, but has no language adapted for this.

Personally I think PHP is rather neat :-) And Ajax after you get used to it is not awefully complicated, especially if you have readymade code to modify.

All in all, good luck! :)

I agree, php on its own is clean, but does not control anything on the UI unless you re-display the whole page at every query. still a bit old fashioned to do an application in 5 days...
None of these things are complex on their own, it's just that it makes dev very lengthy.
and thanks for the luck, I may need it!