Question

我正在尝试从数据库中获取我们的用户列表，以及与他们来自同一队列的人数-在这种情况下，它们被定义为同时来自同一所医学院。

medical_school_id存储在doctor_record表中 graduation_dt也存储在doctor_record表中。

我设法使用子查询写出该查询，该查询执行一个select语句，计算每行中其他行的数量，但这要花很多时间。我的逻辑告诉我，我应该先运行一个简单的GROUP BY查询，然后再以某种方式将medical_school_id加入其中。

按查询分组如下

select count(ca.id) , cdr.medical_school_id, cdr.graduation_dt
from account ca
LEFT JOIN doctor cd on ca.id = cd.account_id
LEFT JOIN doctor_record cdr on cd.gmc_number = cdr.gmc_number
GROUP BY cdr.medical_school_id, cdr.graduation_dt

长选择查询为

select a.id, a.email , dr.medical_school_id,
                     (select count(ba.id) from account ba
                    LEFT JOIN doctor bd on ba.id = bd.account_id
                    LEFT JOIN doctor_record bdr on bd.gmc_number = bdr.gmc_number
                    WHERE bdr.medical_school_id = dr.medical_school_id AND bdr.graduation_dt = dr.graduation_dt) AS med_count,


from account a
LEFT JOIN doctor d on a.id = d.account_id
LEFT JOIN doctor_record dr on d.gmc_number = dr.gmc_number

如果您可以将我推向正确的方向，那就太好了

Answer 1

我认为您只需要窗口功能：

select a.id, a.email, dr.medical_school_id, dr.graduation_dt,
       count(*) over (partition by dr.medical_school_id, dr.graduation_dt) as cohort_size
from account a left join
     doctor d
     on a.id = d.account_id left join
     doctor_record dr
     on d.gmc_number = dr.gmc_number;

Answer 2

对分组依据使用相同的代码：

SELECT * FROM (
(

SELECT   acc.[id]
       , acc.[email]
FROM  
   account acc
LEFT JOIN 
   doctor doc 
ON 
   acc.id = doc.account_id
LEFT JOIN 
   doctor_record doc_rec 
ON 
   doc.gmc_number = doc_rec.gmc_number

) label

LEFT JOIN 
(

SELECT  count(acco.id) 
      , doc_reco.medical_school_id
      , doc_reco.graduation_dt
FROM 
   account acco
LEFT JOIN 
   doctor doct 
ON 
   acco.id = doct.account_id
LEFT JOIN 
   doctor_record doc_reco 
ON 
   doct.gmc_number = doc_reco.gmc_number
GROUP BY 
   doc_reco.medical_school_id, 
   doc_reco.graduation_dt

) count

ON 
count.[medical_school_id]=label.[medical_school_id]
AND
count.[graduation_dt]=label.[graduation_date]

)

Answer 3

这样的事情怎么样？

val df = (p1, p2, p3) match {
    case (Some(x), Some(y), Some(z)) => getRules(x, y, z)
    case _ => throw new Exception("One or more values were NONE!")
}

从计数中减去1，这样就不会在“同一队列中的其他人”中计数医生了
我将“相同的队列”定义为“相同的医学院和毕业日期”。
我不清楚GMC号码是什么以及如何关联。与队列有关吗？

sql子查询加入分组

3 个答案: