campaign.campaign_type='TEMPLATE' or
(
(select count(*) from salesperson_assignment where
salesperson_assignment.user_id = :user_id and
(
(salesperson_assignment.value_type = 'CAMPAIGN' and campaign.id = salesperson_assignment.value_id)
or
(
salesperson_assignment.value_type = 'ADVERTISER' and salesperson_assignment.perm_scope = 'FULL' and
campaign.advertiser_id = salesperson_assignment.value_id
)
or
(
salesperson_assignment.value_type = 'AGENCY' and salesperson_assignment.perm_scope = 'FULL' and
(select agency_id from advertiser a where a.id = campaign.advertiser_id LIMIT 1) =
salesperson_assignment.value_id
)
)
) > 0
)
刚才写的一条SQL。。。啊
大家都改用SQL开发吧，-_-bbbbb
就事论事来说，orm和sql复杂度是一样的，我假设你关注数据本身，当然写法会更elegant，而不是关注数据的availabiltiy，对declarative的语言，不能要求太多。
我是Object Relationship Mapping的拥护者，希望多用Object级别的操作来解决，也比较cache-friendly。。
说起来前两天刚看到flickr的DBA写的一篇blog，有兴趣也可以看看
http://mysqldba.blogspot.com/2007/11/when-starting-out-building-application.html
这条还好啦，都是bool判断的组合而已，逻辑不算复杂，只不过每个域都很长，拼起来ms比较难看而已。最恶心的sql应该是内嵌sql+表连接，又绕又难看，倒是可以出很多智力题。
It’s not intuitive at all, hard to read and understand. I doubt even myself wouldn’t understand this SQL at the first glance after several weeks. But sub select has to be used sometimes…
erm.. i think its poor format to have select statement inside your where clause..
i learned that the hard way when i crashed my server working at bmo with a 200line query filled with select statements inside my where clauses for filtering purposes on the webpage..