MySQL查询复杂ORDER BY

Question

我有以下查询：

SELECT id, title, adcontent, adtargetURL, locationpage, 
locationarg, locationid, displayorder, visible, schedstart, 
schedstop, created, modified, createdby, modifiedby 
FROM ads    
ORDER BY locationpage, locationarg, locationid, title 

我需要订购的字段方式如下：

• 排序与“所有的价值的任何领域locationpage '第一，那么剩下的以升序
• 然后通过在与任何NULL或空字符串值locationarg第一，然后在递增
• 其余然后通过locationid与任何NULL第一或0的值，其余的SC
• 和内的那些，排序由displayorder的“1”，然后再NULL，则“2”
• 以及最后，通过在ASC标题如果任何这些管理对全部相同

我的ORDER BY应该怎样实现这个目标？

这是我到目前为止有：（从下面更新）

ORDER BY locationpage='all', 
     locationpage ASC, 
     locationarg ASC, 
     locationid ASC, 
     displayorder='1', 
     ISNULL(displayorder), 
     displayorder='2', 
     title ASC 

...但是这是行不通的！

Answer 1

你最好的选择是使用一个计算的字段会根据您的规则生成订单ID。我将在稍后添加一个例子..

select 
case 
    when locationpage = "all" then 10 
    when ISNULL(locationarg) then 20 
    .... 
    else 50 
end as OrderID, 
id, 
title, 
.... 

FROM ads    

ORDER BY OrderID DSEC 

Answer 2

给这一个bash：

select id, title, adcontent, adtargetURL, locationpage, locationarg, locationid, displayorder, visible, schedstart, schedstop, created, modified, createdby, modifiedby 
from ads 
order by case when locationpage='all' then 0 else 1 end, 
     locationpage, 
     case when locationarg is null or locationarg='' then 0 else 1 end, 
     locationarg ASC, 
     case when locationid is null OR locationid='0' then 0 else 1 end, 
     locationid, 
     case when displayorder =1 then 0 when displayorder is null then 1 when displayorder = 2 then 2 else 3 end, 
     title;