Table: swimming_champs_2009
Columns: date
event
heat_semifinal_final
nation
time

Question: What nation has a time of 51.35 in the final heat?
SQL: SELECT "nation" FROM swimming_champs_2009 WHERE "time" = '51.35' AND "heat_semifinal_final" = 'final'

Question: Which heat, semifinal or final has a time of 48.97?
SQL: SELECT "heat_semifinal_final" FROM swimming_champs_2009 WHERE "time" = '48.97'

Question: What heat, semifinal or final has a time of 25.00?
SQL: SELECT "heat_semifinal_final" FROM swimming_champs_2009 WHERE "time" = '25.00'

Question: What date was the men's 100m breaststroke in heat 6?
SQL: SELECT "date" FROM swimming_champs_2009 WHERE "event" = 'men''s 100m breaststroke' AND "heat_semifinal_final" = 'heat 6'