Writing PostgreSQL Functions in C++

Question

I have some problem writing postgres functions in C++ while following the guides for C: C-Language Functions. I found that most postgres functions are written in C instead C++, but I have to use a lib that is written in C++, so I chose C++. My question is, is there anything to notice when writing in C++? It's common to write makefiles using pgxs, so how should I write the makefile to make it work? Thanks.

Answer 1

If you can avoid doing it, do so. PostgreSQL doesn't mix especially well with C++. It's possible, as shown by PostGIS, but it's not overly fun.

If you can, write or generate a pure C wrapper to your C++ library and use that wrapper to interact with the library. That won't be practical if it's heavily template based (eg: boost) or uses other more advanced C++ features, but works well if it's just C-with-objects style code. SWIG can help generate wrappers for you.

If you'd prefer to avoid the wrapper approach or if your library is a bit too complex, too exception-reliant, etc for that then you should read this PostgreSQL manual entry.

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