Microsoft Interview Questions

DAO (Data access object ) is used for accessing data before ado it was used for database installed on same sys where the application resides.

RDO (Remote data object ) is used for accessing remote data

ADO (Active data object ) most powerful till date it is nothing but combination of both DAO and RDO 

Tree view control is designed to display data that is hierarchical in nature, such as organization trees, the entries in an index, the files, directories on a disk. It is often used in conjuction with the List view control, which is used to display the contents of the folder selected in the tree view.

List view control displays data as listitem objects. The control excels at representing subsets of data or discrete objects.The list view property is often used in association with a tree view control.

- When u build connection with database through coding, then its ADODB.When u build connection with database through ADO component, then its ADODC.

- ADODB is a ActiveXdll and ADODC is a ActiveXcontrol.

- No Need to bind with controls in ADODB whereas in ADODC we should bind with controls.

DDE (Dynamic Data Exchange) a communication protocol that let applications call each other.

OLE was the first protocol that enabled users and programmers to create compound documents?that is documents that contain data from different applications (for example an Excel worksheet inside a Word document).

A system call is a function.subroutine which interrupts the currently executing program and transfers control to the interrupt routine.The contents of the executing program are saved and after the interrupt routine finishes its function,control is transferred back to the executing program. If we talk in the context of Linux then System calls are called kernel mode.

Whereas API (Application Programming Interface) is a function or a set of functions, objects, protocols or data-structures for the support of application development for developers/programmers. It is actually a kind of function definition which specifies how to make available of a specific service of the system/OS to the other program/process or system. Read more at: https://www.queryhome.com/48442/os-what-is-difference-between-system-call-and-api

ActiveX DLL:

It is an in process server. It runs within the application time.

ActiveX Exe:

It is an out of process server. MS-Excel is an activex exe.

when u call the excel from the vb application u can in the task manager an excel exe will run, whereas for dll u can't see like that.

Visual Basic is not support Inheritance and Data binding OOPS Concept 

Marshalling is the process of packaging and sending interface method parameters across thread, process or machine boundaries.

It is not necessary when the client and the server are on the same computer.