Table: tv_episodes_47
Columns: no_in_series
title
directed_by
written_by
original_air_date
production_code

Question: How many different production codes does the episode originally aired on October 18, 1984 have?
SQL: SELECT COUNT("production_code") FROM tv_episodes_47 WHERE "original_air_date" = 'October 18, 1984'

Question: What's the title of the episode with production code 104?
SQL: SELECT "title" FROM tv_episodes_47 WHERE "production_code" = 104

Question: How many different titles does the episode originally aired on September 27, 1984 have?
SQL: SELECT COUNT("title") FROM tv_episodes_47 WHERE "original_air_date" = 'September 27, 1984'

Question: What's the production code of the episode originally aired on February 21, 1985?
SQL: SELECT MIN("production_code") FROM tv_episodes_47 WHERE "original_air_date" = 'February 21, 1985'

Question: When did the episode titled "Bad dreams" air for the first time?
SQL: SELECT "original_air_date" FROM tv_episodes_47 WHERE "title" = '"Bad Dreams"'

Question: When did the episode titled "Vanessa's new class" air for the first time?
SQL: SELECT "original_air_date" FROM tv_episodes_47 WHERE "title" = '"Vanessa''s New Class"'