On Fri, Mar 24, 2006 at 04:00:35PM -0500, Tom Lane wrote: > Amos Hayes <[EMAIL PROTECTED]> writes: > > I'm trying to build a query that among other things, returns the > > minimum and maximum values contained in either of two columns. > > I think you might be looking for > > select greatest(max(columnA), max(columnB)) from tab; > select least(min(columnA), min(columnB)) from tab; > > greatest/least are relatively new but you can roll your own in > older PG releases.
And if you care about performance you might also try: SELECT max(greatest(column_a, column_b) ... SELECT min(least(column_a, column_b) ... There may be a difference in performance between the two. -- Jim C. Nasby, Sr. Engineering Consultant [EMAIL PROTECTED] Pervasive Software http://pervasive.com work: 512-231-6117 vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461 ---------------------------(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
