Table: cherono_mercy_results
Columns: year
competition
venue
position
event

Question: Which Year has a Venue of bydgoszcz, poland, and an Event of junior team?
SQL: SELECT AVG("year") FROM cherono_mercy_results WHERE "venue" = 'bydgoszcz, poland' AND "event" = 'junior team'

Question: Which Venue has a Year smaller than 2009, and an Event of 3000 m, and a Competition of world youth championships?
SQL: SELECT "venue" FROM cherono_mercy_results WHERE "year" < 2009 AND "event" = '3000 m' AND "competition" = 'world youth championships'

Question: Which Year has a Competition of commonwealth youth games?
SQL: SELECT AVG("year") FROM cherono_mercy_results WHERE "competition" = 'commonwealth youth games'