You can create only directly assigned attributes in the Data Modeler.
Attribute names may not be more than 10 characters in length. Only alphanumeric characters and underscores may be used.
The attribute category is used to indicate the purpose of an entity type. Press F4 to obtain a list of possible entries. An attribute can be assigned a maximum of two categories.
Assign existing data element, name known
Enter the name of the data element.
Assign existing data element, name not known
Position the cursor on the empty data element field and click on the arrow that appears to the right of the entry field to access the ABAP/4 Repository Information System. The selection screen for data elements is displayed.
Enter your selection criteria in the selection screen and choose Program
Assign existing data element, part of name known
Enter the part of the name you know into the input field and use * to represent the part of the name you do not know. Click on the arrow to the right of the entry field. A hit list is displayed.
Using the cursor, select a data element and pressENTER .
Create and assign data element
Enter a name for the new data element. Then double-click on the name to access the ABAP/4 Dictionary. You can now create a new data element. You can read how to do this in the documentation for the ABAP/4 Dictionary. Once you have saved, checked, and activated your data element, click on Back to return to the Create Attributes screen.