how to make a trigger deferrable

Hi,

I have a trigger in my database that checks to see if there is another 
record in the table, and when there is if the type is correct. (if the 
first one is of type "parent", the other has to be of type "child").

When updating these records in a transaction, the trigger only works when 
I make it deferrable. I hacked this by updating pg_trigger and setting the
column  tgdeferrable to true.

IS there a way to do this in SQL? I can only find documentation on setting 
a constraint to deferrable, but not on a trigger.

TIA,
Reinoud

-- 
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"Nothing is as subjective as reality"
Reinoud van Leeuwen    reinoud.v@n.leeuwen.net
http://www.xs4all.nl/~reinoud
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