有sql高手吗？能不能帮我看下这个sql语句

[宝宝的笨熊]

有sql高手吗？能不能帮我看下这个sql语句又没有别的写法总感觉很怪！

select ms.uid,ms.lastip,mmc.username,mmc.extcredits4 from pre_common_member_status as ms left join (select m.uid,m.username,mc.extcredits4 from pre_common_member as m left join pre_common_member_count as mc on mc.uid=m.uid where m.uid='1439' and mc.uid is not null) as mmc on ms.uid=mmc.uid where m.uid='1439'

[GameWong]

能说明下想完成什么逻辑吗

[testmelody]

把你的数据库字段贴出来看看，然后说下需求。你那个语句有问题~

[快溜]

select ms.uid,ms.lastip,m.username,mc.extcredits4
from pre_common_member_status ms 
left join pre_common_member m on ms.uid=m.uid
left join pre_common_member_count mc on mc.uid=m.uid
where ms.uid='1439' and mc.uid is not null

[宝宝的笨熊]

[Quote=引用 2 楼 gamewong 的回复:]
能说明下想完成什么逻辑吗
[/Quote]


就是3张表 pre_common_member，pre_common_member_count，pre_common_member_status
需要查询 pre_common_member（username），
pre_common_member_count（extcredits4），
pre_common_member_status（lastip），
他们用一个共有的字段uid


我要查询出来的结果 ：

uid lastip username extcredits4
1439 60.170.0.70 wodentt 984

想知道还有没有比我这样写简单的sql语句了

[宝宝的笨熊]

[Quote=引用 4 楼 ssp2009 的回复:]
SQL code
select ms.uid,ms.lastip,m.username,mc.extcredits4
from pre_common_member_status ms
left join pre_common_member m on ms.uid=m.uid
left join pre_common_member_count mc on mc.uid=m.uid
whe……
[/Quote]

我的写法存在不存在问题呢? 虽然结果是对的

[SQL77]

select ms.uid,ms.lastip,m.username,mc.extcredits4
from pre_common_member_status ms 
inner join pre_common_member m on ms.uid=m.uid
inner join pre_common_member_count mc on mc.uid=m.uid
where ms.uid='1439' 

[TheGodOfGods]

都用inner join 不用判断空值

select ms.uid,ms.lastip,mmc.username,mmc.extcredits4 
from pre_common_member_status as ms 
inner join (
	select m.uid
	from pre_common_member as m 
	inner join pre_common_member_count as mc 
	on mc.uid=m.uid 
	where m.uid='1439' 
) as mmc 
on ms.uid=mmc.uid 

[宝宝的笨熊]

学习了 谢谢 楼上朋友们帮我解答