Table of Contents
This frontend library is built on top of the
libpq frontend library, which defines
PostgreSQL™'s C API.
Therefore this manual will sometimes refer to the
libpq documentation rather than repeat what is
said there. This was not done to annoy you, but to ensure that the
libpqxx™ documentation remains up-to-date
with any changes in the C frontend. Please bear with us.
Furthermore, if you're ever in doubt about how to use the basic
features of libpqxx™, take a look at the
example programs provided; they're called
test000, test001 etc.
Those should help give you an idea of how simple the library can be
in practice. Don't let that keep you from submitting a request for
improved documentation though; your questions define what this
tutorial needs to say!
All definitions made by libpqxx™ reside
in a namespace pqxx. If you're not familiar
with C++ namespaces, you have two options:
Always import the whole of the pqxx
namespace in your programs.
This tells the compiler to always look in the
pqxx namespace when trying to resolve a name
that doesn't occur in the global (ie. the "default") namespace).
To do this, include the directive
using namespace pqxx;
near the top of each source file that uses
libpqxx™. This is typically best for
your source files (you're probably doing it already for the
std namespace), though it is not considered
good practice in header files.
Explicitly qualify each libpqxx™ name
with the pqxx namespace.
This will tell the compiler exactly which names are supposed to
be in the pqxx namespace, avoiding any
confusion over multiple classes or functions used in your
program possibly having the same name. As long as they're in
different namespaces, the compiler will be able to tell them
apart without trouble. To do this, write
pqxx::connection instead of
connection,
pqxx::result::const_iterator instead of
result::const_iterator, and so on.
This is the mode of address you will typically want to use in header files, to avoid polluting the namespaces of the actual source files with the definitions of the extra namespace.