Indeed, exclusion constrains are really neat! FTR, here's their description in the PostgreSQL manual: http://www.postgresql.org/docs/9.1/static/sql-createtable

Indeed, exclusion constrains are really neat! FTR, here's their description in the PostgreSQL manual: http://www.postgresql.org/docs/9.1/static/sql-createtable.html#SQL-CREATETABLE-EXCLUDE http://www.postgresql.org/docs/9.1/static/sql-createtable.ht...