MIDAS applications

Aggregates.Dpr shows an aggregate field in a client dataset. The aggregate field totals up the ItemsTotal field and displays it on the form's caption. As ItemsTotal fields get modified, the aggregate is updated and so is the form's caption.

MasterDetail.Bpg contains two projects, a MIDAS server and client. The server application has a pair of tables that are set up as master and detail. The provider has been set to automatically provide detail records with the master data. In the client application, a new dataset field has been added into the client dataset using the fields editor to represent the detail table. The detail table is displayed both in a separate grid, and also in a popup grid displayed when you select the dataset field in the master grid, and press the ellipsis button (or press Ctrl+Enter).

This project group also demonstrates the ability of a MIDAS server to add custom information to the data packet. In the server application, the provider's OnGetDataSetProperties adds the custom information. In the client, the client dataset's GetOptionalParam method extracts the information.

Check out the many sample MIDAS applications supplied with Delphi 4 in the DEMOS\MIDAS subdirectory.

DEMOS\MIDAS\INTRCPT is an example of a socket interceptor, which is used to compress/decompress data as it comes in and out of the sockets using the ZLIB compression stuff.

DEMOS\MIDAS\ADHOC shows how to get a MIDAS client to execute ad hoc queries on the server and get the results.