A set is a flexible structure for depicting hierarchies and quantities.
The set ID is only unique when used in combination with the table name.
Set IDs can contain letters, numbers as well as the special characters '_' (underscore) and '-' (hyphen). Please note the following:
Sets whose name begins with a number are delivered with the system or are created by special applications. In general set maintenance, you cannot create them, you can only display, change or delete them. If the first number is 0, you can only display the set.
Groups that were created in controlling are also stored technically as sets. They can however, not be displayed or changed in set maintenance. However, you can use groups, for example, in single and multiple sets as well as in Report Writer reports.