Hai Pratap
In ABAP context , interfaces are only of two types.
1) INBOUND interfaces
2)OUTBOUND Interfaces.
INBOUND:(from external system data is fetched as flat files which is moved to SAP database tables).
in this process we get data in the form of flat files(.txt or .xlx). we will read this data from the files using FM like UPLOAD/WS_UPLOAD/GUI_UPLOAD into internal
tables. And using BDC methods or LSMW tool, we will update the database tables with this data.
OUTBOUND:(Data from SAP dtabase is retrieved adn stored as flatfiles on presentaion server or application server)
In this process we retrieve data using select statements from the database tables and will populate the internal tables. based on the requirement, we will use FM like DOWNLOAD/WS_DOWNLAOD/GUI_DOWNLOAD to write data from internal tables to flat files on th presentation server.
*the above mentioned Fm will work for files on presentaion server(local file system) . IF u want to handle files on the application server, use DATASET.
Other technologies that u mentioned like RFC, BAPI, EDI,ALE, IDOCS etc might be used as apart of interface code.
Regards
Sreeni
