Database schema:

CREATE TABLE tags (
	"index" INTEGER -- example: ['0', '1'],
	id INTEGER -- example: ['0', '2'],
	tag TEXT -- example: ['funk', '1970s'],
	PRIMARY KEY ("index"), 
	CONSTRAINT fk_tags_torrents FOREIGN KEY(id) REFERENCES torrents (id)
)


CREATE TABLE torrents (
	"groupName" TEXT -- example: ['spiderap / a corona jam', 'superappin&#39;'],
	"totalSnatched" INTEGER -- example: ['239', '156'],
	artist TEXT -- example: ['grandmaster flash & the furious five', 'ron hunt & ronnie g & the sm crew'],
	"groupYear" INTEGER -- example: ['1979', '1980'],
	"releaseType" TEXT -- example: ['single', 'album'],
	"groupId" INTEGER -- example: ['720949', '728752'],
	id INTEGER -- example: ['0', '1'],
	PRIMARY KEY (id)
)

Question: Find the average number of downloads for Single-Tables released by '2Pac' between 2001 and 2013.
Evidence: 2Pac is an artist; releaseType = 'single'; between 2001 and 2013 refers to groupYear between 2001 and 2013; average number of downloads = AVG(totalSnatched);

SQL:
SELECT AVG(totalSnatched) FROM torrents WHERE artist LIKE '2Pac' AND releaseType LIKE 'Single' AND groupYear BETWEEN 2001 AND 2013