user: Question: When University of North Carolina at Charlotte is the school what is the lowest enrollment in 2012?
Columns: ['School', 'Location(s)', 'Control', 'Type', 'Enrollment (2012)', 'Founded']
Types: ['text', 'text', 'text', 'text', 'real', 'real']
Sample row: ['Appalachian State University', 'Boone', 'Public', "Master's University", 17589.0, 1899.0]
SQL:

assistant: SELECT MIN("Enrollment (2012)") FROM "Table" WHERE "School" = 'University of North Carolina at Charlotte';