Question:

Do you know any Oracle facility to query easily an Oracle client?
Easily means to me "with a graphical user interface": such just dragging&dropping from the database schema and selecting statements to be applied.

Answer 1:

Seagate Analysis should do it, and it's free. Following is the link to download:

http://www.zdnet.co.uk/software/fstore/M/C/0011MC.html

Answer 2:

Nothing from Oracle.  Try TOAD (www.toad.com) or EZSQL (www.ezsql.net).