MySQL 查询 SELECT 多行

Question

我有下表:

surveys
comp_id    question
4          What is your name?
4          How are you?
4          Where do you live?
5          Who are you?
5          What is your birthday?

我需要帮助编写一个查询来提供以下输出:

comp_id    my_questions
4          What is your name?How are you?Where do you live?
5          Who are you?What is your birthday?

谢谢

Answer 1

您正在寻找GROUP_CONCAT()函数。像这样使用它:

SELECT comp_id, GROUP_CONCAT([DISTINCT] question [ORDER BY some_field ASC/DESC] [SEPARATOR '']) as my_questions
FROM surveys
GROUP BY comp_id

注意，我已经展示了一些可选值，以传递到 [] 中的 GROUP_CONCAT。要完全像您所显示的那样，只需使用GROUP_CONCAT(question SEPARATOR '')。可选项目可让您查找不同的问题值或按任何字段(包括问题本身)对它们进行排序。