>> WHERE (a,b) OVERLAPS (c,d) >> >> to >> >> WHERE (a-1,b+1) OVERLAPS (c-1,d+1) >> >> Will this give correct results ? > > It might give you false positives... > > 2006-11-30 -- 2006-12-05 AND 2006-12-06 -- 2006-12-15 (original) -- > FALSE > 2006-11-29 -- 2006-12-06 AND 2006-12-05 -- 2006-12-16 (changed) -- > TRUE Jorge, Thank you very much. Now I try to William Leite Araújo solution by replacing WHERE (a,b) OVERLAPS (c,d) with WHERE ( c BETWEEN a AND b ) OR ( d BETWEEN a AND b ) Is this OK ? This requires writing a and b expressions twice. How to avoid repeating expressions ? Andrus.
