Salesforce: Query on Group and GroupMember

Group object is quite unique as it stores multiple types of data, from Public Group, Queue, Role, etc., you can see all the Type values in this article Group.

Note: The Type for Public Group is Regular

Sample query: SELECT Type, COUNT(Id) FROM Group GROUP BY Type

For user members in Group and Queue can be a query to the GroupMember object. Sample query:

All queue with queue members
SELECT Id, GroupId, Group.Name, UserOrGroupId FROM GroupMember WHERE Group.Type = 'Queue'

All public group with public group members
SELECT Id, GroupId, Group.Name, UserOrGroupId FROM GroupMember WHERE Group.Type = 'Regular'

All inactive users in a queue or public group
SELECT Id, GroupId, Group.Name, Group.Type, UserOrGroupId FROM GroupMember WHERE UserOrGroupId IN (SELECT Id FROM User WHERE IsActive = false) ORDER BY Group.Name

Reference:

• GroupMember
• Group