plpgsql cursors : dynamic or static?

Hi:
 Are cursors in plpgsql dynamic or static?
 For example :
 ... /* some code */ FOR rec in   SELECT f1,f2               FROM table1 WHERE .... LOOP
   /* some codes that manipulate table1 */ END LOOP;
 Do the result set pointed to by the cursor remains
the same even if performed some data manipulation
inside the FOR..LOOP?

Thank you in advance,

ludwig.



__________________________________________________
Do you Yahoo!?
New DSL Internet Access from SBC & Yahoo!
http://sbc.yahoo.com