if object_id('[TBA]') is not null drop table [TBA]
go
create table [TBA] (id int,name nvarchar(2))
insert into [TBA]
select 1,'A' union all
select 2,'B' union all
select 3,'C'

if object_id('[TBB]') is not null drop table [TBB]
go
create table [TBB] (id int,test nvarchar(2))
insert into [TBB]
select 2,'A' union all
select 4,'B'

select * from [TBA]
select * from [TBB]


SELECT ISNULL(TBA.id,TBB.id) AS  id,NAME,test
FROM dbo.TBA
FULL JOIN TBB ON TBA.id = TBB.id

/*
id    NAME    test
1    A    NULL
2    B    A
3    C    NULL
4    NULL    B*/