Fulltext search is case-insensitive. Note that the search
engine may currently take up to several weeks to update for
new articles.

rickblock wrote:

To clarify, this request has to do with "go", not "search". I understand
"search" is case-insensitive. "Go" is not. If you read the description of what
"go" does (from the link provided above), it includes a step that does not
currently happen but perhaps did in some previous version. If this "go"
behavior could be reintroduced, it would be helpful.

Go performs several case-sensitive checks, then runs search.
It has never been any different.

rickblock wrote:

Would it be possible to add the check described as step 5 at
http://meta.wikimedia.org/wiki/MediaWiki_User%27s_Guide:_The_Go_button, before
running search but after the case sensitive checks currently made?
Specifically, the check is described as "try a case insensitive title search
that also matches partial page titles". I'm less interested in partial page
title matches than the case insensitive search part if that makes a difference.

That's what the search does. It can't be run directly against the
database because the fields are not case-insensitive.

rickblock wrote:

(sorry to be a pest about this - I promise this is the last comment) Even though the fields are currently case-sensitive can't
they have a case-insensitive index - either as a secondary index (I don't know if the DB supports multiple indices to the
same records) or with a duplicate case-insensitive record? If neither of these are feasible, I'll update the description at meta
(and en:) about how "go" works (I'll delete step 5, since the next thing it does is simply "search") and continue
recommending folks add a redirect as a workaround.