Hi Sandip,
In BI4, there is two more flat files type: unstructured text and unstructured binary.
According to the designer guide, unstructured text can process text-based files including text, HTML and XML. (process with the long datatype)
Unstructured biinary can process text-based files including PDF and graphics for instance. (process with the blob datatype)
Please refer to the designer guide section 6.10 for details.
http://help.sap.com/businessobject/product_guides/sboDS41/en/sbo411_ds_designer_en.pdf
(No such features before BI4)
Regards,
Gordon