The grammar root defines the root of the message's segment grammar that a table is mapped to and from. You cannot map columns in the table from other segments above the grammar root you selected.
To set the grammar root:
In the Table Grammar panel, double-click Lab Results. A dialog window appears, reminding you that you have to first set the grammar root.
Click OK. The Grammar Root Selection window appears.
Selecting the Grammar Root
Select Message, and click OK. The Table Mapping window appears.
Close the Table Mapping window for now. You will map the data later in this section.
The next step is to change the maximum mapping repeat limit.