Row-Limit per Group

I need to sum() the 3 biggest values from a specific field of each group.
Using
SELECT sum(numbers) FROM table GROUP BY field
operates on every row and LIMIT only restricts the final result. What I need is a way to limit the rows per group.select sum(numbers)
from daTable as X
where ( select count(*)
from daTable
where numbers > X.numbers) < 3|||This only gives a single amount, i.e., the sum of the biggest three from the whole table.
To obtain the sums of the three biggest values from each group:SELECT field, sum(numbers)
FROM daTable as X
WHERE (SELECT count(*)
FROM daTable
WHERE field = X.field AND numbers > X.numbers) < 3
GROUP BY field|||well spotted, peter, you are quite right, i misunderstood the question

:)