用id关联 表一关联表二,表二关联表三
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select distinct * --要改成查询结果的列名,比如a.F_PrjName
from T_ThirdPrj c
join T_SecondPrj b on c.S_Prjid=b.T_Prjid
join T_FirstPrj a on b.F_Prjid=a.T_Prjid
select distinct * --要改成查询结果的列名,比如a.F_PrjName
from T_ThirdPrj c
join T_SecondPrj b on c.S_Prjid=b.T_Prjid
join T_FirstPrj a on b.F_Prjid=a.T_Prjid