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select a.*,c.*
from a
left join b on a.id=b.id
left join c on a.id=c.id
select a.*,c.*
from a
left join b on a.id=b.id
left join c on b.id=c.id
declare @a table (fid int,fnamea varchar(20))
declare @b table (fid int,fnameb varchar(20))
declare @c table (fid int,fnamec varchar(20))
insert @a
select 1,'a1'
union all select 2,'a2'
union all select 3,'a3'
union all select 2,'a2'
insert @b
select 1,'b1'
union all select 2,'b2'
union all select 4,'b4'
union all select 2,'b2'
union all select 4,'b4'
insert @c
select 1,'c1'
union all select 2,'c2'
union all select 4,'c4'
union all select 5,'c5'
union all select 2,'c2'
union all select 4,'c4'
union all select 5,'c5'
select *
from @a a
left join @b b on a.fid=b.fid
left join @c c on a.fid=c.fid
select *
from @a a
left join @b b on a.fid=b.fid
left join @c c on b.fid=c.fid