> > I'm trying to use a rule to maintain a last_changed field.
>
> Use a trigger, not a rule. You can adjust the last_changed
> field before the tuple is stored that way. There's an example
> in the manual's discussion of triggers.
My original choice was to use a trigger, but I don't want to introduce
C code when I don't have to. I don't believe that making external calls
should be necessary for a query that can be so simply expressed in SQL.
And from the manual: "The procedure name is the C function called"
If triggers can use SQL, I'd be happy to use them, but I can't find a single
example or description on how to do this.
