text: create table viw.tOwnGroup
  (
  	OId int identity(0,1),
  	UserId int not null,
  	GroupId int not null,
  
  	constraint Pk_tOwnGroup primary key(OId),
  	constraint FK_tOwnGroup_tUser foreign key(UserId) references viw.tUser(UserId) ON DELETE CASCADE,
  	constraint FK_tOwnGroup_tGroup foreign key(GroupId) references viw.tGroup(GroupId)
  
  );
  
  GO
  
  create index IX_tOwnGroup_UserId on viw.tOwnGroup(UserId) where UserId <> 0;
  create unique index IX_tOwnGroup_GroupId on viw.tOwnGroup(GroupId) where GroupId <> 0;
  insert into viw.tOwnGroup(UserId, GroupId) values(0,0);