A data group link ties the rows of this data group to corresponding rows in another. Then, as the main data group (the one linked to) is process in, for example an fDocs template generation, as the main data base moves row by row, the linked data group (this one) is positioned on the row that matches it.
For example, if one data group contains a client name, address, and postcode, and a second group contains a postcode and the details of the parish that postcode is in, the parish details can be linked to the client details. You can then add a data item to the client data group to bring across the corresponding parish.
To link a data group to another, simply select the data group to link to and then the field in each data group that must match to join them together.
Any number of data groups may be linked to a particular main data group.
This is a powerful facility when a DSD contains data from different sources that cannot be joined in the gathering process but need to be considered as a single source row. This is different from Merged data groups which merges rows into a larger set of rows.