Question

我正在尝试运行包含三个表的SQL语句。

收入

-id
-title
-amount
-company_id

公司

-id
-name
-sector_id

扇区

-id 
-name

你可以看到＆＃39;收入＆＃39;表与＆＃39;部门没有直接关系。表。我想做的是通过IndustrySectors获得总收入。

到目前为止，我已经设法计算了两个表，但知识限制为三个。请指导我。

这是两张桌子。按公司收入

    $x=0;
    foreach($companies as $Company){
        $companyName= $Company['Company']['name'];
        $companyId= $Company['Company']['id'];

        $query= $this->Income->query("
        SELECT  SUM( amount ) AS IncomeTotal
        FROM incomes
        WHERE company_id=$companyId
        ");

        $total=$query[0][0]['IncomeTotal'];

        if($total!=null){
            //$incomeByCompany[$companyName]=$total;
            //$incomeByCompany['total']=$total;
            $incomeByCompany[$x]['companyId']=$companyId;
            $incomeByCompany[$x]['name']=$companyName;
            $incomeByCompany[$x]['total']=$total;

        }
        $x++;
    }

Answer 1

SELECT s.name , SUM(i.amount) as total_sector
FROM sectors s
JOIN companies c
   ON s.id = c.sector_id
JOIN incomes i
   ON c.id = i.company_id
GROUP BY s.name

除了循环外，您的公司查询应该是：

SELECT c.name , SUM(i.amount) as total_sector
FROM companies c
   ON s.id = c.sector_id
JOIN incomes i
   ON c.id = i.company_id
GROUP BY c.name

通过部门的总金额（包括公司）

1 个答案: