What is the Venue of the Heptathlon after 2006 where Tatyana Chernova comes in Position 7th?
CREATE TABLE "achievements" (
  "year" real,
  "competition" text,
  "venue" text,
  "position" text,
  "notes" text
);
SELECT "venue" FROM "achievements" WHERE "year">2006 AND "position"='7th' AND "notes"='heptathlon';