Trigger question

  I have to write a trigger for table A which goes like this ...

TABLE A
 id number
 seq number
 low number
 hi number

TABLE B
 id number
 low number
 hi number

 Table A can have entries like

 1,1,4,7 and 1,2,1,5.

 When Table A is changed (new row, update or delete) then the range of low and hi must be copied to Table B. In the example above, Table B should have values 1,1,7 for id,low and hi.

 If an update occurs, the minimum value of any low entries with matching id's in Table A must be written to Table B. The maximum value of any hi entries with matching id's in Table A must be written to Table B. For deletes, Table B must also be updated accordingly.

 How might I do this? (mutating table error seems to be the big problem in this case)

-- 
Keith Shave
Management Information Services
Ph:  (204) 945-7937
Fax: (204) 948-2542