On Thu, Aug 9, 2018 at 01:11:05PM +0300, KES wrote: > Bruce: > >Yes, it would work, but doing that only for equality would be > >surprising > to many people > > Why surprising? It is > [documented](https://www.postgresql.org/docs/current/static/sql-create > table.html#sql-createtable-exclude): > >If all of the specified operators test for equality, this is > >equivalent to a UNIQUE constraint, although an ordinary unique > >constraint will be faster. > > Thus the UNIQUE constraint is just particular case of exclusion > constraint, is not?
Well, for me a UNIQUE constraint guarantees each discrete value is unique, while exclusion constraint says discrete or ranges or geometric types don't overlap. I realize equality is a special case of discrete, but having such cases be marked as UNIQUE seems too confusing. -- Bruce Momjian <br...@momjian.us> http://momjian.us EnterpriseDB http://enterprisedb.com + As you are, so once was I. As I am, so you will be. + + Ancient Roman grave inscription +
