yes if you will read line by line using a variable then load the line as per the counter variable.
You can refer his link to understand the logic of using a variable http://john-goodwin.blogspot.in/2009/06/odi-series-processing-all-files-in.html
- Create a filter on your source datastore.
- Apply this filter on "STAGING" area (not source), if your source datastore is a file
- Use the syntax :
col_A = col_A (any column) AND rownum in (1,2,3)
(I assume you're on oracle database)
For 3 last rows, you have to count the number of rows before and store it in a variable (named #row_count for instance)
And in your filter, you write "rownum in (#row_count, #row_count-1, #row_count-2)