> They're adjacent, they don't overlap. Check the documentation on OVERLAPS, > I'm sure it's explicit about whether it is inclusive or exclusive (the > latter apparently). 8.2 doc does not explain term overlap. It only says: "This expression yields true when two time periods (defined by their endpoints) overlap" >> How to make overlaps to return correct result? > > select 1 where ('2006-10-30'::date, '9999-12-31'::date) OVERLAPS > ('2006-10-16'::DATE, '2006-10-31':: DATE); In real queries I have column names and parameters instead of data constants. The only way it seems to replace OVERLAPS operator with AND, OR, <= operators. Is it so ? Andrus.