Actually, I have once (must be about a year ago) started to implement this (as a excercise for search-query, and to perhaps use it). I never really used it though, and was not sure if REGEXP should indeed be a FieldCompareConstraint.
I could check-in my progress (still lingering here) and test it (in mysql and posgresql) a bit, to grant the wish. But I think at least Rob must agree (because it is his code), and perhaps it would even require a VOTE. Kees submitted the wish, I'm not sure why he wants to use regexps, and which database he uses. So, I'd like some feed-back, about this. Michiel -- Michiel Meeuwissen mihxil' Mediacentrum 140 H'sum [] () +31 (0)35 6772979 nl_NL eo_XX en_US