The ability to create table instances in DBA is controlled by the privileges assigned to the group that the current user belongs to.
If you are an administrator of a catalog, and you have Create Table privileges on one of its table definitions, you can use DBA to create a new table instance based on that table definition. When creating the new instance, you can select any COBOL data file for which the table definition has been designed, and then immediately preview that data with the table definition applied.
Administrators with this privilege can also delete table instances from the catalog, even those created at design-time in the Relativity Designer.