I can help you get started with your project, but first, please, provide more information. Do you have to keep your database in MS Notepad files, or can you create datalog files in LabvIEW to serve as your databases. Things are much easier for you if you can work directly with LabvIEW data structures, which are saved into datalog files with full retention of the data types. Reading, scanning, sorting, and all of those sorts of activities are much easier when working directly with LabVIEW data structures. You could then create a special routine that parses your data into any structure you wish for the benefit of other users.
I am not very familiar with common database structures. I build databases as I have mentioned above, using LabVIEW datalog files. It may not be as efficient as a true "database" structure, but unless you are talking about large amounts of data distributed over various servers, I would think that the datalog file would suffice.
Please, define the relational characteristics of these databases. Does database1(message data) just contain lists of messages within a matrix of lookup parameters? What is node data? Is this also just a list of identifiers or strings? I beg your pardon, but I need you to describe your task in more generic programming terms, a lower level than the database structure. Once we get beyond this initial communication gap, I can help you.
You said, "in my application I need to have a dialog box with the VEHICLE.VCF extention." I need a more careful explanation of this. Do you mean that your dialog box must produce a file named VEHICLE.VCF? Do you mean that your dialog box is a file dialog that filters candidate files by the .VCF extension?
You said, "database1(message data) this needs to have few massages chosen from the main database1 and should be able to save them in background." It sounds like you want the user to be presented with a list of messages, which you have drawn from database1. You want the user to be able to select an arbitrary number of these messages and save them to a file?
I will stop here. If you still need help, please, try to be more specific. It is hard to design the entire application from this brief description. Perhaps you should pick a single task and ask how that one task might be accomplished. We could proceed from there.
jc
Mac 10.4
LV7.1
CLD