I haven't installed the Oracle Database Client. I wanted a minimal setup.
I downloaded the Oracle Instant Client SDK and Basic and now it works with Visual Studio. I found out that Oracle ships it only for Visual Studio. I read something about, that it might work with cygwin, but it doesn't really work. All I get is this:
$ g++ -L/cygdrive/e/instantclient_12_1/sdk/lib/msvc/ -I/cygdrive/e/instantclient_12_1/sdk/include/ OracleSqlTest.cpp -ociw32 -loci -loraocci12
/tmp/cce5RtIc.o:OracleSqlTest.cpp:(.text+0x37): undefined reference to `oracle::occi::Environment::createEnvironment(oracle::occi::Environment::Mode, void*, void* (*)(void*, unsigned int), void* (*)(void*, void*, unsigned int), void (*)(void*, void*))'
To my knowledge that means, that those libs (compiled with VC) aren't compatible with my cygwin g++. Is that right?