You can execute Java methods either on a client or on a server, which is a consideration for element storage and hybrid storage. Document storage involves little or no processing of the document.
Element storage – if you map individual elements of an XML document to SQL data, in most cases the XML document is larger than the SQL data. It is generally more efficient to assemble and disassemble the XML document on the client and transfer only the SQL data between the client and the server.
Hybrid storage – if you store both the complete XML document and extracted elements, then it is generally more efficient to extract the data from the server, rather than transfer it from the client.