兩個類似SQL的查詢結果，之前不曾注意

兩個類似SQL的查詢結果，之前不曾注意

select a.*, case when x.resno is null then 0 else 1 end as isown from prm_res a

left join 

(select b.resno from prm_res b

inner join prmg_role_res c on b.resno=c.resno

inner join prmg_acct_role d on d.roleno=c.roleno and d.acct=1

) as x

on a.resno=x.resno where a.sysno=1;

select a.*, case when x.resno is null then 0 else 1 end as isown from prm_res a

left join 

(select b.resno from prm_res b

inner join prmg_role_res c on b.resno=c.resno

inner join prmg_acct_role d on d.roleno=c.roleno and d.acct=1

) as x

on a.resno=x.resno and a.sysno=1;

誰知道啥狀況？歡迎留言