php - 我们可以合并两个查询，将结果返回为行

Question

这里我想获得两个表值的总和，我的表名称是datas和abc_datas。首先，我获取了 datas 表的结果，如下 -

$query1 = $this->db->query("SELECT *, SUM(amount) AS total_sum
         FROM datas
         WHERE user_id = $user_id")->row();

接下来我获取了abc_datas的结果，如下-

$query2 = $this->db->query("SELECT *, SUM(amount) AS total_sum
         FROM abc_datas
         WHERE user_id = $user_id")->row();

现在我想组合这两个查询，并通过组合 total_sum 返回总计。例如，如果第一个表的 total_sum 为 500，第二个表为 1000，我希望输出为 1500 但仅提取第一个查询值

这是我写的最后一个查询 -

$query = $this->db->query("SELECT *, SUM(amount) AS total_sum1
     FROM datas
     WHERE user_id = $user_id
     UNION ALL
     SELECT *, SUM(amount) AS total_sum2
     FROM abc_datas
     WHERE user_id = $user_id;")->row();
    return $query;

我像这样更改了查询以获得所需的输出 -

 $query =$this->db->query("SELECT
 (SELECT SUM(amount) as total_sum1 FROM datas WHERE    user_id=$user_id) + (SELECT SUM(amount) as total_sum2 FROM abc_datas WHERE user_id=$user_id) as total_sum,(SELECT SUM(agent_amount) as total_agent_amount1 FROM datas WHERE    user_id=$user_id) + (SELECT SUM(agent_amount) as total_agent_amount2 FROM abc_datas WHERE user_id=$user_id) as total_agent_amount,(SELECT SUM(profit) as total_profit1 FROM datas WHERE    user_id=$user_id) + (SELECT SUM(profit) as total_profit2 FROM abc_datas WHERE user_id=$user_id) as total_profit
 FROM dual");
 return $query->row();

Answer 1

这是结果

 $query = $this->db->query("SELECT SUM(amount) AS total_sum
        FROM   (SELECT   amount FROM datas WHERE    `user_id`=$user_id
                   UNION ALL
                SELECT amount FROM abc_datas WHERE    `user_id`=$user_id) s");
   return $query->row();