Table: tv_ratings_8
Columns: episode
first_broadcast_denmark_dr1
official_tns_gallup_ratings
first_broadcast_uk_bbc_four
official_barb_ratings

Question: When was the first UK broadcast for episode 9?
SQL: SELECT "first_broadcast_uk_bbc_four" FROM tv_ratings_8 WHERE "episode" = 9

Question: When was the first UK broadcast for the episode with an official TNS Gallup rating of 1575000?
SQL: SELECT "first_broadcast_uk_bbc_four" FROM tv_ratings_8 WHERE "official_tns_gallup_ratings" = 1575000

Question: When was the first UK broadcast when the official Barb ratings was 1085000?
SQL: SELECT "first_broadcast_uk_bbc_four" FROM tv_ratings_8 WHERE "official_barb_ratings" = 1085000