>How 2 make a TCP/IP connection to certain site to check the newest version and
>update it if found the version is old.
>
>This may be huge task as the table structure may charge!

I suggest that you should maintain a database of versions on the remote site describing what's the current version. This hould be downloaded from the remote site. It can then be compared to the items actually found on the local system; if differences are found, you'll have to either download a newer version or download a program that will convert from an older format to a newer format; you'll have to write the conversions between various versions to operate serially, or to deal with each possible older format to convert to the new format. SDT is a commercial tool that makes revising database, table and view related items considerably easier; you provide metadata describing the current format, and SDT manages most conversion and update issues automatically. Obviously, things that involve populating or restructuring exisitng fields will have to be hand-written in most cases.

it's a tremendous undertaking; I've written systems to do this before for clients, and it represents a considerable investment in developing a suitable scripting and data conversion capability. The communications issue of using TCP/IP is insignificant compared to the data maintenance task. My experience is that developing the necessary toolset represents several hundred hours of time, and then for each update, someone has to create the necessary conversion apps to work with the update scheme.