Other values in the TYPE field don't matter.
The name of the group is in the NAME field. More importantly is the ID in the IDENTITY_MAP table. That ID links back to the GROUP_ID in the SEM_CLIENT table. Thus every machine with SEP installed has an entry linking the GROUP_ID back to the name of the group as defined in the IDENTITY_MAP table.
As an example, there is no Group name defined in the SEM_CLIENT table. The best you can do is
SELECT computer_name, group_id from SEM_CLIENT
To get the name of the group that the machine belongs to you have to do a JOIN.
SELECT SEM_CLIENT.COMPUTER_NAME
, IDENTITY_MAP.NAME
FROM IDENTITY_MAP INNER JOIN
SEM_CLIENT ON IDENTITY_MAP.ID = SEM_CLIENT.GROUP_ID