Problem with a script hanging

Good day,

I am having a problem today with a script hanging in an apparently endless loop. At least, that's what I think it is. My Script:

WHENEVER SQLERROR EXIT SQL.SQLCODE; DECLARE
       ExchRate NUMBER;
BEGIN

       SELECT "Rate"
         INTO ExchRate
         FROM evans.exchangerate
        WHERE "EntryDate" = (
              SELECT MAX("EntryDate")
                FROM evans.exchangerate
              );

       UPDATE evans.linkdata
          SET "BPQ CDN" = ROUND (NVL ("BPQ US", 0) / ExchRate, 4)
        WHERE "BPQ CDN" IS NULL
           OR "BPQ CDN" = 0;

END This is an excerpt from the script, the remainder is similar update statements on this and other tables in my database. What's happening today is that my process is getting hung up on the first update and doesn't go any further.

I had the same problem when I tried to rebuild this as a procedure so I wouldn't have to run it externally. At that time, I thought that it was because it was converted a procedure that caused this lockup.

Given what you see above, do you have any ideas as to what could be causing this routine to lock up?

-- 
Ken Rachynski
Database Analyst
EVANS
http://evansonline.com/