>Oh No! It's dangerous. I prefer replace only the records modified.

Why dangerous? If you're worried, back up the original before you overwrite it. It seems to me that you want the "master" table to be exactly the same as the "temp" - if so, an overwrite is the surest way to achieve this.

If you really want to update manually you can use a general approach like this:

SELECT ;
  * ;
  FROM Master ;
  UNION ;
  SELECT ;
    * ;
    FROM Temp ;
  INTO CURSOR Changed

* The UNION clause by default removes duplicate rows. You will be left with a list of rows that are either:
* 1. Present in MASTER but not in TEMP
* 2. Present in TEMP but not in MASTER
* 3. Present in both tables, but different

Assuming you have a primary key on each table, you can scan the "Changed" cursor and update appropriately.