Question

我正在努力学习如何实现这张桌子。我希望另一批记录能够制作另一列，如下图所示

这是我的疑问：

    SELECT 
          stud_name, 
          equivalent 
    FROM tb_student_record 
    WHERE instructor_id = 'INST-20131296' 
          AND criteria = 'Quiz' 
          AND description = 'BIOETHICS' 
          AND subj_code = 'N049' 
          AND term = 'Midterm';

任何建议都将不胜感激。

Answer 1

更新了查询：

SELECT 
    stud_name, 
    GROUP_CONCAT(equivalent SEPARATOR '#') as equivalent
FROM tb_student_record 
WHERE instructor_id = 'INST-20131296' 
    AND criteria = 'Quiz' 
    AND description = 'BIOETHICS' 
    AND subj_code = 'N049' 
    AND term = 'Midterm'
GROUP BY `stud_name`;

在php中获取结果并使用explode函数分开。该功能将起作用：

$ equivalent = explode（“＃”，$ yourFetchArr-＆gt;等效;）//依赖于你的提取，我使用mysql_fetch_object();

现在$equivalent[0]和$equivalent[1]是两个独立的等价物;

Answer 2

你可以做一个子查询应该看起来像这样

SELECT 
          stud_name, 
          equivalent,
          (SELECT 
               equivalent 
              FROM tb_student_record 
              WHERE instructor_id = 'INST-20131296' 
                AND criteria = 'Quiz' 
                AND description = 'BIOETHICS' 
                AND subj_code = 'N049' 
                AND term = 'Midterm';) AS equivalent2
    FROM tb_student_record 
    WHERE instructor_id = 'INST-20131296' 
          AND criteria = 'Quiz' 
          AND description = 'BIOETHICS' 
          AND subj_code = 'N049' 
          AND term = 'Midterm';

然后只需更改内部查询以选择查询的详细信息。如果您给我更多详细信息，我可以更新我的代码以更正确地反映内部查询

PHP | MYSQL：单个人的2个或更多列

2 个答案: