Marc Mamin-2 wrote > I would misuse GUC variables for this. > (using the functions current_setting and set_config) > > define a set get and switch fuction (I use operators for better > readability) > something like: > > select 'a' ==> 'foo' > 'a' > select 'b' <==> 'foo' > 'a' > select <== 'foo' > 'b' > > > and in your query: > > SELECT > case when test then col <==> 'foo' else <== 'foo' end Is it possible to alter GUC on a record-by-record basis? Is this something you have actually done? Even if it does technically work this seems like a last-resort kind of solution. The syntax (though that could be hidden in a wrapper function) is definitely unusual and the abuse of the GUC system in this manner is surprising. How would this interface with a window function? The main consideration is dealing with multiple partitions and the fact that a window column calculation requires the use of a function while this solution would seem to preclude that. David J. -- View this message in context: http://postgresql.1045698.n5.nabble.com/Detecting-change-in-event-properties-tp5775959p5775975.html Sent from the PostgreSQL - general mailing list archive at Nabble.com. -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general