php form + mysql?

[MicoX]

Well, take this opportunity to introduce me in this forum.
I am a spanish newbie and I need your help.
I've been looking throughout the forum and can not find a solution.
I have the following problem:
I have a form in which data such as dates of arrival and departure, name, address, etc.. I want to record the data were recorded in different databases, for example in form and members, in addition to external databases.
Is there a way?
Sorry for my English ops:

[Ruud]

I'm not sure about several different databases, but all data can be stored in one database. The default form already offers that option (though I never used that). There is also an extension that gives even more DB options: efg

But other then that you'd have to write/find an extension that does that. If you have some PHP experience it might be an option because Contao is extremely flexible and not extremely hard to extend!

[MicoX]

I don´t know what file is called when clicking on the submit button.
I need to find that file to add a database insert.
Could you help me?