[Vince]

pawn Code:

sizeof(array) // First dimension
sizeof(array[]) // second dimension
sizeof(array[][]) // third dimension

In your case, the second dimension would always return 9, though, because that's the highest number of cells.
Basically, your code will compile as:

pawn Code:

new
    array1[3][9] = {
        { 1, 2, 3, 4, 5, 6, 7, 8, 9 }, // there is 9 numbers
        { 1, 2, 3, 4, 5, 0, 0, 0, 0 }, // there is 5 numbers
        { 1, 2, 3, 4, 5, 6, 0, 0, 0 }, // there is 6 numbers
    }
;