Table: tv_episode_data_130
Columns: no_in_series
no_in_season
title
directed_by
written_by
u_s_viewers_millions
original_u_s_air_date
prod_code

Question: which is the production code when the number of the episode in series is 87? 
SQL: SELECT "prod_code" FROM tv_episode_data_130 WHERE "no_in_series" = 87

Question: how many directors had the episode called "magic unmasked"?
SQL: SELECT COUNT("directed_by") FROM tv_episode_data_130 WHERE "title" = '"Magic Unmasked"'

Question: what is the number of the episode in the series whose production code is 405?
SQL: SELECT "no_in_series" FROM tv_episode_data_130 WHERE "prod_code" = '405'

Question: when was the premiere of the episode whose production code is 415? 
SQL: SELECT "original_u_s_air_date" FROM tv_episode_data_130 WHERE "prod_code" = '415'

Question: who were the writers in the episode whose production code was 411? 
SQL: SELECT "written_by" FROM tv_episode_data_130 WHERE "prod_code" = '411'

Question: who were the director of the episode whose number in the season is 17? 
SQL: SELECT "directed_by" FROM tv_episode_data_130 WHERE "no_in_season" = 17