>>>>>>>>>>>> Satheesh Bandaram wrote (2005-03-03 16:39:11): > Yes, Cloudscape used to allow creating UNIQUE indexes on null columns, > but in a non-standard way. Old cloudscape used to allow only one NULL > value in the UNIQUE index, where as, I think the standard required > multiple NULL values.
I think that behaviour was Oracle compliant. > I think making Derby handle multiple NULLs in UNIQUE index needs changes > to store/indexing. Anyway, UNIQUE constraint on possible null columns (SQl-99 Feature T591) is a non-Core SQL-99 feature. -- Bernt Marius Johnsen, HA Data Management, Sun Microsystems, Norway ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ NOTICE: This signature is neither personal, religious, literary, ethnic, racial, offensive nor humorous.
