What is the sum of League Goals, when Position is "DF", when League Cup Apps is "0", when Total Apps is "7", and when FLT Goals is less than 0?
CREATE TABLE "appearances_goals" (
  "squad_no" real,
  "name" text,
  "position" text,
  "league_apps" text,
  "league_goals" real,
  "fa_cup_apps" text,
  "fa_cup_goals" real,
  "league_cup_apps" text,
  "league_cup_goals" real,
  "flt_apps" text,
  "flt_goals" real,
  "total_apps" text,
  "total_goals" real
);
SELECT SUM("league_goals") FROM "appearances_goals" WHERE "position"='df' AND "league_cup_apps"='0' AND "total_apps"='7' AND "flt_goals"<0;