CREATE TABLE table_38081 ("Rider" CLOB, "Manufacturer" CLOB, "Laps" FLOAT, "Time/Retired" CLOB, "Grid" FLOAT)

What is the grid number of Sandro Cortese, who has Aprilia as the manufacturer and less than 19 laps?
SELECT SUM("Grid") FROM table_38081 WHERE "Manufacturer" = 'aprilia' AND "Laps" < '19' AND "Rider" = 'sandro cortese'
SELECT SUM("Grid") FROM "table_38081" WHERE "Laps" < '19' AND "Manufacturer" = 'aprilia' AND "Rider" = 'sandro cortese'