user: Question: I want the total number of Grids for heinz-harald frentzen
Columns: ['Driver', 'Constructor', 'Laps', 'Time/Retired', 'Grid']
Types: ['text', 'text', 'real', 'text', 'real']
Sample row: ['David Coulthard', 'McLaren - Mercedes', 58.0, '1:30:28.718', 4.0]
SQL:

assistant: SELECT SUM("Grid") FROM "Table" WHERE "Driver" = 'heinz-harald frentzen';