Improving partial lookup results

Peter Bowyer peter at
Fri Sep 20 15:36:00 BST 2019

Hi Olly,

On Wed, 18 Sep 2019 at 22:09, Olly Betts <olly at> wrote:

> If you really wanted to wildcard expand all words in a query string,
> you'd have to parse it yourself, turn each word into an OP_WILDCARD
> query and combine those.

Now you say it, that makes total sense (and seems so obvious). Testing, it
matches as I want it to for "p bow".

> I'd think that's likely to create a lot of false matches though, and
> wildcards are relatively expensive so you might want to limit how many
> words get wildcarded in a single query to avoid problems.

I was aiming to work round the false matches by also doing an exact match
of the word(s) with a higher ranking factor. So if what's being wildcarded
has an exact match also, it ranks higher.

> There's expanded support for wildcards on git master, so you could
> create an OP_WILDCARD query for `*ann*`, though that seems even more
> likely to result in a lot of false matches and will tend to be more
> expensive too.

Yes, I'm discarding this idea. Others are more important.


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