mysql - MySQL查询选择多行

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，它给我以下输出：

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

您正在寻找该GROUP_CONCAT()功能。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的值来传递到 GROUP_CONCAT 中[]。要获得与您展示的完全一样的信息，请使用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。