Just to clarify 

1. You can add triggers to non-sql files so long as they have a header. See the 
HELP SQL CREATE TRIGGER for the subroutine layout.

2. You can have up to 6 main triggers -before and after each type of event 
(insert, update, delete).

3. triggers must be globally cataloged since the file may be updated from any 
account - so a local catalog wouldn't be found.

4. To globally catalog copy the CATALOG entry from the VOC of the uv account to 
your local VOC (under a new name) and use that. Prefix the catalog name with an 
asterisk.

5. Triggers impose some limitations : they all make sense if you step back and 
think about them except (b):

a. They observe some SQL constraints for isolation - so ALL writes must be lock 
protected.

b. You can't move the file to a new platform (format.conv won't process it)

c. Some commands are disallowed.

d. No interaction is allowed, including the RAID debugger.

6. A useful tip - If a trigger changes you must ensure no-one has the file 
open. That's not always possible on a 24x7 system so I have a master trigger 
read a list of subtriggers from a file and call them in turn.

Then I can back out a change by removing a routine from the list, or substitute 
a new routine at any time.

7. Triggers slow processing if over-used.

Brian
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