[TYPO3-english] How to add dynamically new database tables and columns

[Hauke Hain]

Hi there,

I want to create an extension that adds dynamically new database tables and 
new columns to existing tables.
First I thought of overwriting ext_tables.sql / ext_tables.php but that is 
no good idea because of extension updates...

Do you have any hint where I should look? Is there a cool TYPO3 function for 
doingt this?
How would you solve this issue?

Of couse I want TYPO3 to know the new datatables and columns and not deleted 
by the database analyser of the install tool.

I am curiously looking forward to your answers.

Hauke