4D has a "Create new data segments as needed" option in Preferences to automatically create new data segments when the maximum size of the data file or its segments is reached during database operation. The maximum size is 2 GB for the data file and 2 GB by default for each segment, within the limit of 128 GB.

To select that option:
1. Go to the design anvironment
2. From the edit Menu, select Preferences.
   The Preferences dialog is displayed.
3. Select the Database panel.
4. Check the option "Create new data segments as needed."
5. Click OK.

Each automatic segment is stored next to the last segment created. The automatic segment's name is based on that of the data file. For a data file named MyData.4DD, the first segment is named MyData.4DS, the second MyData2.DS and so on.

This option does not prevent manual creation of segments. Segments created automatically will appear in the segments management dialog box in User mode.