> On another point, isn't XOR a standard SQL boolean operator?
Well, it is not included in the table of logical operators in O'Reilly's `SQL in a Nutshell' (Table 3.7, p123, an edition published in 2001). Though this is not definitive, of course.
Clive.
Clive Davenhall Institute for Astronomy, e-mail (internet, JANET): acd @ roe.ac.uk Royal Observatory Edinburgh, fax from within the UK: 0131-668-8416 Blackford Hill, Edinburgh, fax from overseas: +44-131-668-8416 EH9 3HJ, Scotland.Received on 2004-02-09Z16:26:06