Re: Rules/Trigges Trade-offs

Bruce,

> > 1) Rules can't use indexes to do their processing, so Rules which query
large
> > secondary tables can be a bad idea (maybe this has changed?)
>
> I don't think this is true. Rewrite is before optimizer so it should be
> optimized just the same.

I was speaking if the Rule has to do a lookup on a 2nd table in the course of
its processing; it used to be that such a lookup could not use indexes
because Rules are pre-optimizer. This could have changed since 7.1, though.

> > 3) There are no AFTER Rules, making, for example, a rule with a table
check on
> > the new data impractical, so you'd want to use Triggers or Constraints
>
> We have changed ordering in 7.3 where I think INSERT rules are _after_
> the insert.

How would that work? What if I want to reject the insert?

--
-Josh Berkus
Aglio Database Solutions
San Francisco