On Wed, Feb 14, 2018 at 8:44 AM, Clemens Ladisch <[email protected]> wrote:
> Dominique Devienne wrote: > > in https://www.sqlite.org/src/info/f3112e67cdb27c1a > > to fix above ticket, I see queries with order by +a, > > but in https://www.sqlite.org/lang_select.html#orderby > > I don't see any obvious mention about that +. > > "Unary plus" does not change the value: > > sqlite> select 1; > 1 > sqlite> select -1; > -1 > sqlite> select +1; > 1 > > It's used to change the expression from a column reference to something > that is computed, which means that SQLite cannot use an index for it > (unless you created an expression index on +a): > <http://www.sqlite.org/optoverview.html#uplus> Thanks. That's interesting. But then, why use it in this context? Why DRH wants to purposely bypass the index in this case? How is that relevant to testing tuple / row-values comparisons? --DD _______________________________________________ sqlite-users mailing list [email protected] http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
