Muhammad Shahzad

你可以用 GROUP_CONCAT :

SELECT person_id,
   GROUP_CONCAT(hobbies SEPARATOR ', ')
FROM peoples_hobbies
GROUP BY person_id;

正如路德维希在 his comment, 您可以添加 DISTINCT 操作员要避免重复:

SELECT person_id,
   GROUP_CONCAT(DISTINCT hobbies SEPARATOR ', ')
FROM peoples_hobbies
GROUP BY person_id;

正如Jan在 their comment, 也可以在使用 ORDER BY :

SELECT person_id, 
       GROUP_CONCAT(hobbies ORDER BY hobbies ASC SEPARATOR ', ')
FROM peoples_hobbies
GROUP BY person_id;

正如Dag在 his comment, 结果有1024字节的限制。要解决此问题,请在查询之前运行此查询:

SET group_concat_max_len = 2048;

当然,你可以改变 2048 根据你的需要。要计算并分配值,请执行以下操作:

SET group_concat_max_len = CAST(
                     (SELECT SUM(LENGTH(hobbies)) + COUNT(*) * LENGTH(', ')
                           FROM peoples_hobbies
                           GROUP BY person_id) AS UNSIGNED);