The Driver Manager completely or partially implements a number of functions and therefore checks for all or some of the errors and warnings in those functions.
The Driver Manager implements SQLDataSources and SQLDrivers and checks for all errors and warnings in these functions.
The Driver Manager checks whether a driver implements SQLGetFunctions. If the driver does not implement SQLGetFunctions, the Driver Manager implements and checks for all errors and warnings in it.
The Driver Manager partially implements SQLAllocHandle, SQLConnect, SQLDriverConnect, SQLBrowseConnect, SQLFreeHandle, SQLGetDiagRec, and SQLGetDiagField and checks for some errors in these functions. It may return the same errors
as the driver for some of these functions, as both perform similar operations.
For example, the Driver Manager or driver may return SQLSTATE IM008 (Dialog
failed) if they are unable to display a login dialog box for SQLDriverConnect.