user: Question: What was the margin of victory at the Mercedes Championships?
Columns: ['No.', 'Date', 'Tournament', 'Winning score', 'To par', 'Margin of victory', 'Runner(s)-up']
Types: ['real', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: [1.0, 'Sep 16, 1984', 'Greater Milwaukee Open', '67-68-69-68=272', '–16', '5 strokes', 'Tom Watson']
SQL:

assistant: SELECT "Margin of victory" FROM "Table" WHERE "Tournament" = 'Mercedes Championships';