On Thu, Feb 17, 2005 at 01:17:16PM -0500, Jan Wieck wrote:
> On 2/16/2005 6:46 AM, Andrew Sullivan wrote:

> >Yes. 
> 
> Actually not exactly. The query executed on the subscriber would be
> 
>     update example_table set key = '4' where key = '4';
> 
> The slony log trigger filters out unchanged columns. If that results in 
> no column change at all (empty SET clause in the update), it adds the 
> first key column so that the update becomes valid SQL.

Sorry, I should have been clearer.  Jan is of course right that the
trigger filters unchanged columns; but the OP wanted to know if it
filters out queries which do no work or have no effect.  The answer
to that, as far as I know, is no, and Jan's example above illustrates
it.

A

-- 
Andrew Sullivan  | ajs at crankycanuck.ca
I remember when computers were frustrating because they *did* exactly what 
you told them to.  That actually seems sort of quaint now.
		--J.D. Baldwin