LEFT JOIN后接条件和where后接条件的区别

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LEFT JOIN  on   后面接 and 条件
例 : LEFT JOIN OA_FLOW of on fa.FLOW_ID = of.ID    and of.STATE = '0' ;
和
通过where接条件的区别
例 : LEFT JOIN OA_FLOW of on fa.FLOW_ID = of.ID    where of.STATE = '0';

sql一、

SELECT 
fa.ID,fa.APPLY_ID ,
of.FLOW_NAME,of.CREATE_TIME
from FLOW_APPLY fa 
LEFT JOIN OA_FLOW of on fa.FLOW_ID = of.ID 
and of.STATE = '0';
下面为查询结果

sql二、

SELECT 
fa.ID,fa.APPLY_ID ,
of.FLOW_NAME,of.CREATE_TIME
from FLOW_APPLY fa 
LEFT JOIN OA_FLOW of on fa.FLOW_ID = of.ID 
where of.STATE = '0';
下面为查询结果

总结：  sql一 可以查询出主表结果，但是附表结果不会显示 sql二 都不会显示