MySQL -- 行转列 -- GROUP_CONCAT -- MAX(CASE WHEN THEN)

SELECT
    `name`,
    MAX(
        CASE 
        WHEN  course=‘语文‘ THEN
            score
        END
    ) AS 语文,
    MAX(
        CASE 
        WHEN course=‘数学‘ THEN
            score
        END
    ) AS 数学, 
    MAX(
        CASE 
        WHEN course=‘英语‘ THEN
            score
        END
    ) AS 英语
FROM
    student
GROUP BY `name`
;

SELECT
    `name`,
    GROUP_CONCAT(course, ":", score) AS 成绩
FROM
    student
GROUP BY
    `name`;

-- 合并字段显示 ： 去重、排序
SELECT rid,GROUP_CONCAT(DISTINCT gid ORDER BY gid)
FROM gt_lighting.res_lights
GROUP BY rid;