SQLAllocConnect Mapping

When an application calls SQLAllocConnect through an ODBC 3.0 driver, the call to SQLAllocConnect(henv, phdbc) is mapped to SQLAllocHandle as follows:

1 The Driver Manager allocates a connection and returns it to the application.

2 When the application establishes a connection, the Driver Manager calls

SQLAllocHandle(SQL_HANDLE_DBC, InputHandle, OutputHandlePtr)

in the driver with InputHandle set to henv, and OutputHandlePtr set to phdbc.