DBI defines an interface for communication between R and relational database
management systems.
All classes in this package are virtual and need to be extended by
the various R/DBMS implementations (so-called DBI backends).
Arguments
Definition
A DBI backend is an R package
which imports the DBI
and methods
packages.
For better or worse, the names of many existing backends start with
‘R’, e.g., RSQLite, RMySQL, RSQLServer; it is up
to the backend author to adopt this convention or not.
DBI classes and methods
A backend defines three classes,
which are subclasses of
DBIDriver,
DBIConnection,
and DBIResult.
The backend provides implementation for all methods
of these base classes
that are defined but not implemented by DBI.
All methods defined in DBI are reexported (so that the package can
be used without having to attach DBI),
and have an ellipsis ... in their formals for extensibility.
Construction of the DBIDriver object
The backend must support creation of an instance of its DBIDriver subclass
with a constructor function.
By default, its name is the package name without the leading ‘R’
(if it exists), e.g., SQLite for the RSQLite package.
However, backend authors may choose a different name.
The constructor must be exported, and
it must be a function
that is callable without arguments.
DBI recommends to define a constructor with an empty argument list.