Mariadb SQL使用分组依据选择计数，然后从另一个中选择不为空的值

Question

我在查询时遇到问题，也许有人可以帮助我：）

我有3张桌子：

1）文件

DocRef  CustRef
Doc1    Cust1
Doc2    Cust2
Doc3    Cust1

2）LinkInter

DocRef  InterRef
Doc1    Inter1
Doc2    Inter2
Doc3    Inter3

3）Inter

id  InterRef    deliverychannel email   mobilenb    date    status
1   Inter1      Email           email1@email.be     2013-01-14T00:00:00Z    ok
2   Inter1      SMS                     0444111111  2013-01-12T00:00:00Z    ko
3   Inter1      Other           email5@email.be     2013-02-21T00:00:00Z    ko
4   Inter2      Email   email2@email.be 044456465465    2013-01-21T00:00:00Z    ko
5   Inter3      Email                               2013-01-21T00:00:00Z    ko
6   Inter3      SMS                                 2013-01-22T00:00:00Z    ko
7   Inter3      Other   email3@mail.be              2013-01-22T00:00:00Z    ko

要获得最佳视图，请点击此处：sqlfiddle

我想要的结果如下：

CustRef | number of InterRef SMS KO| Last email known| Last mobilenb known
Cust1   | 2                        | email5@email.be | 0444111111

我希望所有的客户的交付渠道=“ SMS”，状态为“ ko”，状态为“ KO”的Inter（交互）数，最近的电子邮件已知，最后的移动电话号码。

我尝试使用2个函数getLastEmailKnown和getLastmobilenbKnown，但是我的表计数的记录超过10.000.000，这需要很多时间

我可以在php页面上获得此结果，但这不是解决方案，我只希望有一个查询

如果我分别执行3个查询，它可以工作，但我只想要一个

SELECT d.CustRef, count(DISTINCT i.InterRef) , i.email, i.mobilenb
FROM Documents d
    INNER join LinkInter link on link.DocRef = d.DocRef
    INNER join Inter i on i.InterRef = link.InterRef 
          and i.deliverychannel = 'SMS' 
          and i.status = 'ko'
group by d.CustRef 
Order by d.CustRef DESC;

SELECT distinct i.email as lastEmailKnown, d.CustRef
FROM Inter i
    INNER join LinkInter link on link.InterRef = i.InterRef
    INNER join Documents d on d.DocRef = link.DocRef
where d.CustRef = 'Cust1' AND email is not NULL and email <> '' ORDER by date DESC LIMIT 1;

SELECT distinct i.mobilenb as lastmobileKnown, d.CustRef
FROM Inter i
    INNER join LinkInter link on link.InterRef = i.InterRef
    INNER join Documents d on d.DocRef = link.DocRef
where d.CustRef = 'Cust1' AND mobilenb is not NULL and mobilenb <> '' ORDER by date DESC LIMIT 1;