I would like it that every time I insert a row in table A, another row of the same table must be updated according to the values of the row I'm inserting. What's the best way to do this? It's impossible for me to do it with triggersto update a row of the same table in which I define the trigger.
Try using an intermediary table. Table A has a trigger that updates Table B. Table B has a trigger that updates Table A.
I haven't tried this, and I seem to remember somewhere that the engine will not allow such loops, but it's worth a try.