Hi DVRK,
yes, they are different. See SAP note 1736976, the attachment SAP_BW_on_HANA_Sizing_V2.pdf for more details.
The sizing report reads a sample set of records from the DB, analyzes the sample size in its ABAP representation, and extrapolates the total size of the table if it was entirely loaded into ABAP memory, using the total row count information of the DB. By looking at the ABAP representation, the impact of DB specific features like intrinsic compression or special data formats on sizing is automatically eliminated, and the report can estimate the size of the table in ABAP by applying a suitable compression factor. In the output of the report you can find the ABAP size of tables along with the estimated HANA size. Due to the different representation of data in ABAP and the underlying DB system, the DB table sizes may significantly differ from the ABAP sizes.
Regards,
Candy
