On Thu, Jul 18, 2019 at 9:11 PM Keith Medcalf <kmedc...@dessus.com> wrote:
> Except in SQLite where as a documented behavioural anomaly maintained for > backwards compatibility it simply means "UNIQUE" (for ROWID tables). And > UNIQUE indexes may have NULL components. This is because despite your > wishing that your primary key is the primary key, it is not the primary key. > > However when WITHOUT ROWID tables were introduced there was no backwards > compatibility issues (they were new after all) then PRIMARY KEY could be > implemented as UNIQUE NOT NULL ... > > https://sqlite.org/nulls.html > https://sqlite.org/rowidtable.html > https://sqlite.org/withoutrowid.html > > See especially 2 sub 4 in the latter. > This whole thread is good material for the new(ish) quirks page IMHO. As Keith points out, most of the material exists in the doc already, but IMHO the quirks page should be the one-stop page to learn about all those historical or by-design particularities of SQLite, with a short explanation and pointers to other doc places with more details. Just my $0.02 of course :) --DD _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
