SAP acessando banco de dados externo

• Using transaction SE11, create a table (ZTABLE) with the same fields as the table in the external database, make sure that the type and lengths of the fields are identical.
• Using transaction SE11, create a view (ZTABLE_VIEW, projection view) using BASIS table ZTABLE
• Using SVRMGRL>  (it's not a transaction.. it's a Oracle Utility)

create dblink REMOTE_DB as connect to remote_user identified by password; (database link created)
drop table ZTABLE; (table dropped)
create synonym ZTABLE for ZTABLE@REMOTE_DB; (synonym created)

• Using transaction SE16 , type in ZTABLE_VIEW and hit RETURN
• Enter value in key fields and hit execute. (displays rows from the remote table)

Fonte: http://www.saptechies.com/how-to-access-an-external-database-from-abap-via-dblink-oracle/