inner join 多表查询

三表以及三表以上联合查询：

select table1.ziduan1,table2.ziduan,2,table3，ziduan3
from table1 inner join table2 
on table1.field1 = table2.field1 
inner join table3 
on table1.field1 = table3.field1

　举例：　

select clFile.FILEPATH,clPerson.personcode,cailiao.clcode 
    from clFile inner join clPerson 
    on clFile.PGUID = clPerson.MGUID
    inner join cailiao 
    on clPerson.MGUID = cailiao.clGuid";

俩表联合查询：

select * FROM 
    表1 INNER JOIN 表2 
    ON 表1.字段号=表2.字段号

　举例：

select * from CaiLiao inner 
    join clCode 
    on CaiLiao.clCode=clCode.code 
    where CaiLiao.clGUID 
    in (select mGUID from clPerson where pcode = '123' )