How many yards did kevin swayne average, with a long carry over 7?
CREATE TABLE "running_backs" (
  "player" text,
  "car" real,
  "yards" real,
  "avg" real,
  "td_s" real,
  "long" real
);
SELECT MIN("avg") FROM "running_backs" WHERE "player"='kevin swayne' AND "long">7;