Administrators can domain separate custom tables by adding a sys_domain field to it.

1. Navigate to the table's list view. For example, type <table name>.list in the navigation filter.
2. Right-click the list header and select Configure > List Layout.
3. In the Create new field section, enter sys_domain as the Name and Domain ID as the Type.
4. Click Add.
5. Click Save.
   Note: Any other means of creating a field adds a u_ prefix to the column name. For domain separation to work the column name must be sys_domain without any u_ prefix.