user: Question: What is the minimum pick of a Centre from the Czech Republic?
Columns: ['Pick', 'Player', 'Position', 'Nationality', 'NHL team', 'College/junior/club team']
Types: ['real', 'text', 'text', 'text', 'text', 'text']
Sample row: [27.0, 'Cory Sarich', 'Defence', 'Canada', 'Buffalo Sabres (from Ottawa via St. Louis)', 'Saskatoon Blades (WHL)']
SQL:

assistant: SELECT MIN("Pick") FROM "Table" WHERE "Position" = 'Centre' AND "Nationality" = 'Czech Republic';