DataHub® DDE Client and Server Options

Direct access to Microsoft Office programs
Support for the Microsoft DDE protocol has been one of the fundamental features of the DataHub from its initial development right through to today. The DDE interface within the Cogent DataHub provides both read and write access to programs like Microsoft Excel.

DDE support

• Cogent DataHub can make DDE Advise connections to DDE servers. DDE Advise is an asynchronous mechanism by which the server sends data to the DataHub whenever it changes.
• By default, the Cogent DataHub will act as a DDE server itself, accepting DDE Advise connection requests from other DDE programs.
• When you drag and drop data from the DataHub into an Excel spreadsheet, you automatically configure Excel to establish a DDE Advise connection with the DataHub.
   

Share real-time Excel data with other Excel users
For many years the Cogent DataHub has been used by financial companies to easily share the data generated from one Excel application with other Excel users over a network or Internet connection. These customers used the DataHub under its original name of Cascade DataHub and to the best of our knowledge all of these original systems are still in use today.

The DataHub offers a simple but powerful model for sharing the data produced from a spreadsheet analysis, rather than sharing the spreadsheet itself. This allows for much faster communication between servers and client computers and the ability to fully secure the communication, which is useful when transmitting the data over the Internet.

Three Easy Steps to a Full Read/Write, Networked Excel Connection

Step 1: Read data from Excel
Reading the data out of Excel is usually the first step in the process of networking Excel data. This involves a simple configuration in the DataHub where you define which cells in your spreadsheet contain the data you are interested in. To make the transfer faster and to reduce bandwidth usage, most customers define sometimes large ranges within Excel that get copied to the DataHub.

Step 2: Network the data to another computer
Once the data is in the DataHub, it is a simple procedure to tunnel/mirror this data over to another DataHub running on the client computer. Simply tell the DataHub on the client computer where to look on your network and it will connect to the other DataHub and immediately be sent a complete copy of the data from the server side. Whenever new data is read into the server-side DataHub, it is immediately mirrored to all connected client-side DataHubs.

Step 3: Write data to Excel
The final step in the process is to copy the data from the client-side DataHub into the client user's Excel spreadsheet. This is as simple as dragging the data point from the DataHub and dropping it into the Excel spreadsheet. Save the sheet and the next time you open it, Excel will immediately start receiving data again.

See Case Studies for more examples.