Null Value From Database And Jagged Array

I need to scan database and insert its values into an array. But I'm having some difficulties in handling null values and array.

The database looks like this:
0 1 2 3 4
30 31 32
33 34
36 37 38 39 40
38 39 47 48

I want to make array rr_item which gonna looks like this:
arr_item(1)={0,1,2,3,4}
arr_item(2)={30,31,32}
arr_item(3)={33,34}
arr_item(4)={36,37,38,39,40}
arr_item(5)={38,39,47,48}

Every code I've tried result in error everytime I tried to insert null value into any kind of c=variable, including array which I want to use. And I'm not quite sure with what I'm doing in jagged array I want to build.
sql_list = "SELECT * FROM retail"
oledbCnn = New OleDbConnection(connetionString)
Try
oledbCnn.Open()
[Code] .....