SELECT FROM Files, TagMap, Tags WHERE
(Files.Id=TagMap.FileId AND TagMap.TagId=Tags.Id)
AND
(Tags.Namespace='yuyushiki')

-- Should be SELECT Id FROM

Okay /swt/ here's my best SQL query
SELECT Files.Id, Class, COUNT(*) AS Relevance, Indexed FROM Files, TagMap, Tags, single_image WHERE single_image.Id = Files.Id AND Files.Class = 'single_image' AND Files.Id = TagMap.FileId AND TagMap.TagId = Tags.Id AND ((Member = 'yuyushiki')) GROUP BY Files.Id ORDER BY Relevance DESC, Files.Indexed DESC, Files.Id DESC LIMIT 20 OFFSET 20

This bad boy is generated by a big function that does a lot of string processing. . . how fun!