On Wed, Feb 14, 2018 at 8:44 AM, Clemens Ladisch <clem...@ladisch.de> 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;
> sqlite> select -1;
> sqlite> select +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):
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