On Wednesday, 1 March, 2017 12:21, James K. Lowden <jklow...@schemamania.org> wrote:
> Probably I'm overlooking something, and probably this is not the right > forum. SQLite adheres to the SQL standard; that's established. Why > does the standard say what it does? I'm only saying it's not clear to > me that there's theoretical justification. I believe that Codd originally referred to this as the "Domain" requirement. That is, that a "Parent" specified a domain, and that each "child" (member) must be a part of that domain. Hence the requirement for the "Domain" (Parent) entries to be unique whilst the Child (Member of domain) entries are not, yet have a referent (foreign key) to the relation specifying the domain. _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
