What is the sum of Avg/G for Dan Dierking when the Loss is 0 and the Gain is more than 34?
CREATE TABLE "rushing" (
  "name" text,
  "gp_gs" real,
  "gain" real,
  "loss" real,
  "long" real,
  "avg_g" real
);
SELECT SUM("avg_g") FROM "rushing" WHERE "loss"=0 AND "name"='dan dierking' AND "gain">34;