“创建视图”和 "Other query" 使用 mysql 在 Codeigniter 中合并问题

Question

在 phpmyadmin 中，我运行两个查询都在工作，我得到了我的值，但是当我想在 codeigniter 中执行这个查询时，我遇到了如何使用相同的 function.In 执行两个查询的问题，下面是我的查询。

查询：

create view V_average_marks AS
 select student_id,avg(total_mark) as average_mark from total_marks 
 group by student_id;

SELECT student_id,(average_mark), FIND_IN_SET( average_mark, (
SELECT GROUP_CONCAT( average_mark
ORDER BY average_mark DESC ) 
FROM V_average_marks )
) AS rank
FROM V_average_marks;

当我在 phpmyadmin 上运行时，我得到了我的价值，但当我在 codeigniter.Can 中运行时，我感到困惑，找不到正确的方法。

型号：

public function final_rank()
    {
        $sql = "SELECT student_id,(average_mark), FIND_IN_SET(average_mark,(GROUP_CONCAT( average_mark ORDER BY average_mark DESC)FROM V_average_marks)) AS rank FROM V_average_marks";
        $query = $this->db->query($sql);

        return $query->result_array();
    }

Answer 1

我找到了正确答案：

create view V_average_marks AS
select student_id,avg(total_mark) as average_mark from total_marks 
group by student_id; 

create view V_rank AS
SELECT student_id,(average_mark), FIND_IN_SET( average_mark, (
SELECT GROUP_CONCAT( average_mark
ORDER BY average_mark DESC ) 
FROM V_average_marks )
) AS rank
FROM V_average_marks;

SELECT * from V_rank;

从模型调用 SELECT * from V_rank 这个 sql 你可以得到想要的结果

“创建视图”和 "Other query" 使用 mysql 在 Codeigniter 中合并问题

“create view” and "Other query" merge problem in Codeigniter using mysql

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