ODBC doesn't work directly on wireless (embedded) devices running Microsoft Pocket PC or Mobile 5.0 operating systems. There is at least one commercial dll that will allow mobile devices to send data back and forth to database, but it is quite costly. There is a free DLL from Microsoft that you can get with eVB compiler, but it is pretty darned slow when sending/receiving lots of data. The only other choice I know of, which we took, is to write your own socket program that acts as a bridge (server program) between the wireless device(s) and the database.
if you write your own thing you will need to write two programs:
1. On the database server computer you need a service program (assuming MS-Windows operating system) that receives requests from the wireless device(s), send the requests to the database program, gather the result set(s) and forward the result set(s) back to the wireless devices. You can also write this as a deamon on a *nix box. And the database may reside on the same computer or another remote computer.
2. On the wireless device you need a program that sends sql requests to the server mentioned above and wait for the result. After receiving the result set(s) store the result sets in a format that can be used by the program running on the wireless device. The program I wrote stored the data in files so that they could be used later by any of several programs running on the wireless device. Sort of like writing your own database program. WinCE has its own built-in database manager but its just too slow to be useful for anything larger than some trivel requirements.
thanks for your time. you did mention above about the a program to send SQL request to server. what do you mean by program, i have do it myself or can download somewhere?
I mean a DLL or a static library which contains functions that can be called by the application program. And you will have to write these yourself because those that I am aware of are proprietary and can not be released.
oh, thanks dragon, you really help alot. but i just need to pull small amount of the information from database such as point balance. does it really need to create such a difficult program, or just need to add some code to connect and retrieve data from database?