Question

我有一个postgres查询，我想在其中交换我的array_agg语句：

SELECT client_user_id, 
       (array_agg(question), array_agg(client_intake_question_id), array_agg(answer)) as answer 
FROM client_intake_answer
LEFT OUTER JOIN client_intake_question 
ON       client_intake_question.id = client_user_id
GROUP BY client_user_id

给我以下内容：

 5 | ("{""Have you ever received counselling?"",""Have you ever received counselling or mental health support in the past?""}","{1,2}","{yes,no}")

我希望结果如下：

  5 | ("{""Have you ever received counselling?", 1, "yes"",""Have you ever received counselling or mental health support in the past?", 2, "no""}"

我该怎么做？

Answer 1

我已经设置了一个类似于你的小例子：

create table answers(user_id int, question_id int, answer varchar(20));
create table questions(question_id int, question varchar(20));

insert into questions values
(1, 'question 1'),
(2, 'question 2');

insert into answers values
(1, 1, 'yes'),
(1, 2, 'no'),
(2, 1, 'no'),
(2, 2, 'yes');

select user_id, array_agg(concat(questions.question, ',',  questions.question_id::text, ',', answers.answer))
from   questions
inner join answers
on     questions.question_id = answers.question_id
group by answers.user_id

user_id | array_agg                             
------: | :-------------------------------------
      1 | {"question 1,1,yes","question 2,2,no"}
      2 | {"question 1,1,no","question 2,2,yes"}

dbfiddle here

Answer 2

要将多个array_agg交错或拼接在一起，您可以执行以下操作：

SELECT client_user_id, 
   array_agg('[' || client_intake_question_id || question || ',' || answer || ']') as answer 
FROM client_intake_answer
LEFT OUTER JOIN
client_intake_question ON  client_intake_question.id = client_user_id
GROUP BY client_user_id

在postgres

2 个答案: