A test query for selecting by ticketid

Question

This is a test query to select tickets by ticketid , starting with the most recent, as to get the top5 most recent tickets. There will be still mistakes in it. please don't tell me those about stupid mistakes,and spaces, at first and obvious syntax mistakes. Otherwise I don't learn it. My question has to do with the loop. Do you think it is useful to use a loop for this, or should it stay as it is, or should it be something else.
DECLARE
Define, and open a cursor;
min_ticket NUMBER; -- minimum ticketid
laatste_ticket NUMBER; -- latest ticketid
tussen_ticket NUMBER; -- in between ticket
Query_to_use VARCHAR2(4000);
BEGIN
Select max(ticketid) into laatste_ticketid from ticket;
Select count(*) into teller from ticket where (ticketid<laatste_ticketid ) AND (ticketid>(laatste_ticketid-6));
Select ticketid, categoriecd, titel into cursor from ticket where (ticketid<laatste_ticketid ) AND (ticketid>(laatste_ticketid-6));
Select min(ticketid) into min_ticketid from ticket;
If teller= < 5
     If teller = 5
          Query_to_use := Query_to_use || ';';
          Return Query_to_use;
     else
          --Loop through records from laatste_ticketid to min_ticketid
               Select gebruikerid into te_testen_veld from ticket where ticketid = tussen_ticketid ;
               If te_testen_veld is NULL THEN
                    tussen_ticketid := tussen_ticketid - 1;
                    te_testen_veld := NULL;
               Else
Query_to_use := query_to_use || ' UNION select ticketid, categoriecd, titel from ticket '||
               ' where ticketid = tussen_ticketid ';
               te_testen_veld := NULL;
               Teller := teller + 1;
                    If (teller < 5)
                         tussen_ticketid := tussen_ticketid - 1;
                    Else if (teller = 5)
                         teller := 6;
                    End if;
               End if;
          --End Loop;
     End if;
End if;
Query_to_use := Query_to_use || ';';
Return Query_to_use;
END;

Answer 1

You can get all this using one SQL statement, without resorting to explicit cursors. Have a look at http://asktom.oracle.com and search for Top-N Query.
Depending on what you are doing, you may want to use a cursor for loop.
I assume this is for some sort of electronic queueing system. if you gave us more detail as to what you are trying to do, you may get better advice.