Hi Marc,
Now that my exams are finished :), I have started to look at the script "tbl_select.php" for planning the refactoring.
As the script is used for searching a table using a form in the UI, it contains two sections:-
1. If block that "displays the selection form".
2. else to do the search work.

Looking at the search form display part, it is done using raw HTML-PHP mix with calls to functions from some library files, so first main concern should be to handle the HTML-PHP mix and convert the code into functions. About that I saw the wiki page for Roadmap to 4.0 [0] :-
 "The current <html> and <?php> mix will be cleaned up in the process. The <html> output will be moved to lib/include files which can be called by either the index page or by the specific files (which can still be referenced separately)."

So, to move HTML to lib/include files, slicing proper reusable HTML blocks from the script should be done, followed by moving it to a lib/include file, and then calling the include file at proper places. Is this the way, I should proceed ?

[0] http://wiki.phpmyadmin.net/pma/FOSDEM_2012_Meeting

Regards
--
Atul Pratap Singh
Senior Undergraduate Student
Institute Of Technology,
Banaras Hindu University, Varanasi,
India.