I've got to admit that I'm not an expert on SAP R/3 programming, so this is more of a basic question on that matter.
Is there any way to get a list of accessible RFC modules and/or tables on a SAP system? On many examples on the internet I've found one RFC modul that seems to be available on every SAP system ("SD_RFC_CUSTOMER_GET") and I wonder if there are any more of these standard RFC modules that I can use. I can easily query the SAP system for all SAP-Queries that are available but I just cannot find a way to do this with RFC modules or tables. I cannot even find a list of these RFC modules after searching on Google for hours... so am I missing something or is this just impossible?
Thanks for any help in advance.
For "official" RFC modules, use the transaction BAPI. These modules are well-documented and released for customer and partner use - meaning that you'll get support if something goes wrong. For everything else, you're free to use whatever you find, but don't bother to ask SAP for support, they won't help you.
If you want to look for stuff inside the SAP system, use transaction SE80 (choose "Repository Infosystem" in the left section). Note that on many selection screens, you can expand the parameters. This will show a parameter to search for RFC modules only.
As for tables - you might be interested in the RPY_* function modules as well as the (in)famous RFC_READ_TABLE...
with transaction SE84 you can query for RFC modules/programs/... by their name, description and so on.
for database tables you can for example use the transaction SE11.
One trick I found quick useful is to search for functions with sorting on the number of times the function is used in the SAP code. Functions used more times are more likely to be more reusable and also more likely to have less bugs. Check this post on how to search that way: http://apolemia.blogspot.com/2010/02/finding-functions-in-sap.html