ODCI : oracle data catridge interface service : what shared libs are needed

Question

Hi,
I am writing aggregate functions. For using ODCI along with OCI in C/C++.. what are the shared libraries which are required : i have oci.h & odci.h files but do not know what shared libraries are needed to use the ODCI interface.
I am getting the error :
ORA-06521: PL/SQL: Error mapping function
ORA-06522: /usr/lib/oracle/xe/app/oracle/product/10.2.0/server/lib/custagg.so:
undefined symbol: ODCIAggregateInitialize
ORA-28579: network error during callback from external procedure agent
./libagtsh.so: undefined reference to `homtscb_ShutdownCallback'
I don't see any one responding to my queries.
Can any one give me some other paid forums where I can pay some fee and get clarifications for my errors and doubts.
I am a student trying to study the extendibility of databases with user defined aggregates without the need to change the underlying database engine. This is a part of research which i am doing.

Answer 1

But some how i am having problem with ODCI : it is
not identifying the ODCIAggregateInitialize function
It is throwing error : ORA-06521: PL/SQL: Error
mapping function
ORA-06522:
/usr/lib/oracle/xe/app/oracle/product/10.2.0/server/li
b/custagg.so:
undefined symbol: ODCIAggregateInitializeThat's a pretty useful error message IMHO
And generally in Unix environment we don't include
'extern "C" ' before each member function in the C
program but we do that in Windows environment . So
may be I thought of just try including that in my
program(unix environment) and it was giving me even
a worse error :
RA-28579: network error during callback from external
procedure agent.So I just removed that extern "C"
keyword.Actually, the extern "C" is required because even though you are writing C-like code, it's C++ since there are declarations in the middle of the code, which C doesn't support (maybe C99 does, I don't know). This tells me you compile using a C++ compiler, which mangles the method name (to support method overloading, which C doesn't support). Adding the extern "C" makes the C++ not mangle the method, and thus the ODCI system can find the entry point in your shared lib.
ORA-28579 is not a worse error, it is the error you should fix. But I can't help you there, I've never done it. OTOH, if you can make this work, I'd be very interested if you could post a complete example demonstrating what you are doing. --DD