Help on Trigger

Dear all,
I'm new on this forum and I'm new also about Postgres.
I have to realise a trigger to update one table but i can't understand in which way do it.
I try to explain deeply the question:
when i insert or update the table TABLE1, i want that my trigger do some operation with the inserted record in order to update one or more fields in the same TABLE1.

Thank you in advance for your replay

Michele.

Documentation: http://www.postgresql.org/docs/8.3/static/plpgsql-trigger.html

You need a table (you already have one), a stored procedure (trigger function) and the trigger itself. The trigger has to execute the stored procedure, that's all.

Start learning by using the code in the documentation.

Good luck!