These might be backend specific and not supported in other databases... but there are some popular postgres tricks to deal with this:
* in the constraint, coalesce NULL into an empty string (or other value). * use multiple indexes both are actually discussed in the comments to this question: http://stackoverflow.com/questions/8289100/create-unique-constraint-with-null-columns -- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sqlalchemy+unsubscr...@googlegroups.com. To post to this group, send email to sqlalchemy@googlegroups.com. Visit this group at http://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/d/optout.
