A system administrator, system security officer, or the database owner can use sp_changegroup to change a user’s group affiliation. Each user can be a member of only one group other than “public,” of which all users are always members.
Before you execute sp_changegroup:
The group must exist.
The user must have access to the current database (must be listed in sysusers).
The syntax for sp_changegroup is:
sp_changegroup grpname, username
For example, to change the user “jim” from his current group to the group “management,” use:
sp_changegroup management, jim
To remove a user from a group without assigning the user to another group, you must change the group affiliation to “public”:
sp_changegroup "public", jim
The name “public” must be in quotes because it is a reserved word. This command reduces Jim’s group affiliation to “public” only.
When a user changes from one group to another, the user loses all permissions that he or she had as a result of belonging to the old group, but gains the permissions granted to the new group.
The assignment of users into groups can be changed at any time.
