OT: MoinMoin and Mediawiki?

[Paul Rubin]

cookedm+news at physics.mcmaster.ca (David M. Cooke) writes:
> >> > lists of incoming links to wiki pages,
> ...
> Most Wiki implementations (MoinMoin included) have this, by using a
> search. Usually, following the original Wiki (http://c2.com/cgi/wiki)
> model, you get at it by clicking on the title of the page.
> 
> Searching instead of indexing makes it very resilient :-)

How does it do that?  It has to scan every page in the entire wiki?!
That's totally impractical for a large wiki.