Table: tv_episode_data_17
Columns: series
title
directed_by
written_by
original_air_date
production_code
u_s_viewers_millions

Question: What's the original air date of the episode with production code 2T6719?
SQL: SELECT "original_air_date" FROM tv_episode_data_17 WHERE "production_code" = '2T6719'

Question: Who's the writer of the episode see by 12.13 million US viewers?
SQL: SELECT "written_by" FROM tv_episode_data_17 WHERE "u_s_viewers_millions" = '12.13'

Question: What's the total number of episodes with production code 2T6705?
SQL: SELECT COUNT("title") FROM tv_episode_data_17 WHERE "production_code" = '2T6705'

Question: What's the total number of directors who've directed episodes seen by 11.34 million US viewers?
SQL: SELECT COUNT("directed_by") FROM tv_episode_data_17 WHERE "u_s_viewers_millions" = '11.34'

Question: What's the production code of the episode seen by 11.64 million US viewers?
SQL: SELECT "production_code" FROM tv_episode_data_17 WHERE "u_s_viewers_millions" = '11.64'