Structure
The picture below presents the structure of the library, together with its clients and servers. The boxes filled with cyan represent components that are part of the library distribution.
The SOCI library is extensible in the following ways:
- More backends can be added to target various database servers.
- More interfaces can be defined on top of common backend interface.
- Other languages can use the simple interface, which was designed specifically for the "C" calling convention to ensure easy binding.
The core part of the library and the backend interface definition are placed
in the core directory of the library distribution. The soci-backend.h file
is an internal abstract interface to the actual backends, which are needed to
perform operations on the given database server. Normally, the C++ client
program needs to interface with the soci.h header and the header(s) relevant
to the given backend(s) (for example, soci-oracle.h), although with dynamic
backend loading this can be avoided. It is possible for the same program to use
many backends at the same time.
Everything in SOCI is declared in the namespace soci. All code examples
presented in this documentation assume that your code begins with something like:
#include <soci/soci.h>
// other includes if necessary
using namespace soci;
// ...
Note: In simple programs, #include for the relevant backend is needed only
in the file where the session object is created with explicit name of
the backend factory. The example program on the previous page
shows the appropriate #include directive for the Oracle backend.
It is also possible to name backends at run-time as part of the connection
string, in which case no backend-specific #include directive is necessary.