Which Team has a Previous team of san diego rockets, and a Position of f?
CREATE TABLE "selections" (
  "player" text,
  "pos" text,
  "nationality" text,
  "team" text,
  "previous_team" text,
  "years_of_nba_experience_a" real,
  "career_with_the_franchise_b" text
);
SELECT "team" FROM "selections" WHERE "previous_team"='san diego rockets' AND "pos"='f';