BIP – Query to find size of documents attached in DOR

Oracle HCM provides a functionality to store different kinds of worker documents in Document Records. Over a period of time, a large number of documents get accumulated for different workers. In such cases, there are requirements to know size of attachments in DORs. For, this I have developed a simple query which can be modified as needed:

select fdv.file_name
      ,TRUNC(SUM(wcc_documents.dFileSize)/1024,2) 			as "Size in KB"
      ,TRUNC(SUM(wcc_documents.dFileSize)/1024/1024,2) 		as "Size in MB"
      ,TRUNC(SUM(wcc_documents.dFileSize)/1024/1024/1024,2) as "Size in GB"
 from hr_documents_of_record hdr, 
      fnd_attached_documents fad, 
      fnd_documents_vl fdv,
      fusion_ocserver11g.revisions wcc_revisions,  
      fusion_ocserver11g.documents wcc_documents
where to_char(hdr.documents_of_record_id) = fad.pk1_value(+)
  and fad.entity_name(+) = 'HR_DOCUMENTS_OF_RECORD'
  and fad.document_id = fdv.document_id(+)
  and fdv.dm_version_number = wcc_revisions.did
  and wcc_revisions.did = wcc_documents.did
  and wcc_documents.disprimary = 1
group by fdv.file_name
order by 1