Php 如何将MySQL行折叠为列结果

有一个查询，我想从中获取：

• 附加到当前opportunity记录的用户的用户名

• 与每个opportunity记录关联的销售阶段

• 美元

  与商机记录关联的金额

我想：

• 获取当前的IF语句结果，并将其折叠

当前查询：

$sql = "SELECT u.user_name as USER,
               if(o.sales_stage='Prospecting', o.amount, '') as PROSPECTING,
               if(o.sales_stage='Needs Analysis', o.amount, '') as NEEDS_ANALYSIS,
               if(o.sales_stage='Closed Won', o.amount, '') as CLOSED_WON
          FROM opportunities o,
               users u
         WHERE o.assigned_user_id = u.id
      GROUP BY u.user_name ";

当前结果：

USER   PROSPECTING  NEEDS_ANALYSIS  CLOSED_WON
---------------------------------------------
chris  10000        0               0
chris  0            15000           0
chris  0            0               10000
sara   5000         0               0
sara   0            0               10000 

我想做的是，在我只获得1个用户的情况下，折叠结果，以及每个SalesStage的用户数量

USER   PROSPECTING  NEEDS_ANALYSIS  CLOSED_WON
---------------------------------------------
chris  10000        15000           10000
sara   5000         0               10000

---

您需要在$amounts中添加聚合函数。。。即：

SELECT

u.user_name as USER,

if(o.sales_stage='Prospecting', SUM(o.amount), '') as PROSPECTING,

if(o.sales_stage='Needs Analysis', SUM(o.amount), '') as NEEDS_ANALYSIS,

if(o.sales_stage='Closed Won', SUM(o.amount), '') as CLOSED_WON

FROM

opportunities o,

users u

WHERE

o.assigned_user_id = u.id

GROUP BY

u.user_name

编辑

---

现在我考虑一下，您可能仍然会得到单独的行，因为同一用户的不同记录的销售阶段可能不同。您是否考虑过使用例程对每个销售阶段进行计算，以便将结果向下折叠到每个用户一行？

您可以将当前查询包装到另一个查询中，如下所示：

select subquery.user, 
       sum(subquery.propspecting), 
       sum(subquery.needs_analysis), 
       sum(subquery.closed_won) 
from (*...your query goes here*) subquery 
group by subquery.user

“折叠”通常被称为“旋转”，因为您正在将行转换为列数据。使用：

  SELECT u.user_name as USER,
         MAX(CASE WHEN o.sales_stage = 'Prospecting' THEN o.amount END) AS PROSPECTING,
         MAX(CASE WHEN o.sales_stage = 'Needs Analysis' THEN o.amount END) AS NEEDS_ANALYSIS,
         MAX(CASE WHEN o.sales_stage = 'Closed Won' THEN o.amount END) AS CLOSED_WON
    FROM OPPORTUNITIES o
    JOIN USERS u ON u.id = o.assigned_user_id
GROUP BY u.user_name

---

首先想到的是使用三个不同的别名连接Opportunities表，然后选择适当的别名。fieldname。。。。