What is the lowest enrollment amount for a year left of 2012 and a current conference of Mid-South?
CREATE TABLE "former_members" (
  "location" text,
  "founded" real,
  "type" text,
  "enrollment" real,
  "nickname" text,
  "joined" real,
  "left" real,
  "current_conference" text
);
SELECT MIN("enrollment") FROM "former_members" WHERE "left"=2012 AND "current_conference"='mid-south';