Creating an update trigger on a table

[bessebo]

I have a situation where I have to update a table based on information in the same table.

(example: I have bill-tos and ship-tos in the same table and the field that signifies whether it is a ship-to or a bill-to is called addresstype. I want to set a record called price code in a ship-to equal to the price code that is in the bill-to record that is tied to that shipto. How can I set an update trigger on a table and then perform an update on the same table within that trigger? Won't this set up a recursive reaction and will be in a continuous loop?)

Thanks,
Bessebo