user: Question: Who won the regular season when Missouri Valley Conference took place?
Columns: ['Conference', 'Regular Season Winner', 'Conference Player of the Year', 'Conference Tournament', 'Tournament Venue (City)', 'Tournament Winner']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Atlantic Coast Conference', 'Duke', 'Pete Brennan , North Carolina', "1958 ACC Men's Basketball Tournament", 'Reynolds Coliseum ( Raleigh, North Carolina )', 'Maryland']
SQL:

assistant: SELECT "Regular Season Winner" FROM "Table" WHERE "Conference" = 'Missouri Valley Conference';