Tom Lane <[EMAIL PROTECTED]> writes: > Greg Stark <[EMAIL PROTECTED]> writes: > > The thing is that these opclasses you're describing are closely related. It > > ought to be possible to use a single index to produce results in any of the > > four orders you describe. > > Wrong --- only two of them. You can't magically swap nulls from one end > of the index to the other (and Hannu's flight of fantasy about double > indexscans is just a flight of fantasy; it would be solving the problem > at entirely the wrong place).
I think that was my flight of fantasy. I didn't say it was pretty but it would solve the problem. Whereas having a separate opclass would mean someone would need a second index to satisfy the ordering which seems silly. -- greg ---------------------------(end of broadcast)--------------------------- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match