Hi Venkat,
List the attributes(display or navigational) that are used in the report or in cube.
The below link contains the basic information about G/LAccount master data.
http://help.sap.com/saphelp_40b/helpdata/en/c7/a88a7e43dd11d182b30000e829fbfe/content.htm
Because of ref.Integrity, you first load the master data and then load transaction data.
Thanks