The following documentation comment has been logged on the website: Page: https://www.postgresql.org/docs/11/indexes-unique.html Description:
Sometimes it is convenient to create an unique index that considers NULL values equal. Designating a "zero" value for those rows might not be feasible, for example due to a foreign key. The documentation currently only states that unique indexes do not consider NULLs equal. It might be good to offer workarounds, like indexing a coalesce function, if scans are not the reason for the index, but the uniqueness constraint.
