Table: rail_journeys_episodes
Columns: episode_no
episode_title
uk_broadcast_date
presenter
countries_visited

Question: What episode number is presented by Ben Okri ?
SQL: SELECT "episode_no" FROM rail_journeys_episodes WHERE "presenter" = 'Ben Okri'

Question: What was the UK broadcast date for the episode presented by Buck Henry?
SQL: SELECT "uk_broadcast_date" FROM rail_journeys_episodes WHERE "presenter" = 'Buck Henry'