多行上的MySQL查询组\u CONCAT

我从一般问答数据中获取姓名和地址数据，以创建某种规范化的报告数据库

我得到的查询使用group_concat，适用于单个问题集，但不适用于多个问题集

我试图简化我的工作，只使用名字和姓氏，只使用3条记录，2条记录一个人，1条记录另一个人。事实上，尽管有超过300000条记录

qs.Id=1的结果的数量

在1、2、3中使用qs.Id的结果

我想在1，2，3中看到的qs.Id

那么，如何让第二个示例为每组名称和地址信息返回一个单独的行呢

我意识到当前的数据存储方式有问题，但我无法改变数据存储方式

我可以得到但不确定如何组合其他

我无法更改的简化模式：

CREATE TABLE StaticQuestion (
  Id INT NOT NULL,
  StaticText VARCHAR(500) NOT NULL);

CREATE TABLE Question (
  Id INT NOT NULL, 
  Text VARCHAR(500) NOT NULL);

CREATE TABLE StaticQuestionQuestionLink (
  Id INT NOT NULL,
  StaticQuestionId INT NOT NULL,
  QuestionId INT NOT NULL,
  DateEffective DATETIME NOT NULL);

CREATE TABLE Answer (
  Id INT NOT NULL,
  Text VARCHAR(500) NOT NULL);

CREATE TABLE QuestionSet (
  Id INT NOT NULL,
  DateEffective DATETIME NOT NULL);

CREATE TABLE QuestionAnswerLink (
  Id INT NOT NULL,
  QuestionSetId INT NOT NULL,
  QuestionId INT NOT NULL,
  AnswerId INT NOT NULL,
  StaticQuestionId INT NOT NULL);

一些示例数据仅用于名字和姓氏

INSERT INTO StaticQuestion (Id, StaticText)
VALUES (1, 'FirstName'),
       (2, 'LastName');

INSERT INTO Question (Id, Text)
VALUES (1, 'What is your first name?'),
       (2, 'What is your forename?'),
       (3, 'What is your Surname?');

INSERT INTO StaticQuestionQuestionLink (Id, StaticQuestionId, QuestionId, DateEffective)
VALUES (1, 1, 1, '2001-01-01'),
       (2, 1, 2, '2008-08-08'),
       (3, 2, 3, '2001-01-01');

INSERT INTO Answer (Id, Text)
VALUES (1, 'Bob'),
       (2, 'Jones'),
       (3, 'Bob'),
       (4, 'Jones'),
       (5, 'Frank'),
       (6, 'Smith');

INSERT INTO QuestionSet (Id, DateEffective)
VALUES (1, '2002-03-25'),
       (2, '2009-05-05'),
       (3, '2009-08-06');

INSERT INTO QuestionAnswerLink (Id, QuestionSetId, QuestionId, AnswerId, StaticQuestionId)
VALUES (1, 1, 1, 1, 1),
       (2, 1, 3, 2, 2),
       (3, 2, 2, 3, 1),
       (4, 2, 3, 4, 2),
       (5, 3, 2, 5, 1),
       (6, 3, 3, 6, 2);

为了防止SQLFiddle出现，下面是我链接到的示例中的3个查询：

1:-工作查询，但仅针对1组数据

SELECT MAX(QuestionSetId) AS QuestionSetId,
       GROUP_CONCAT(Forename) AS Forename,
       GROUP_CONCAT(Surname) AS Surname
FROM   (SELECT
            x.QuestionSetId,
            CASE x.StaticQuestionId WHEN 1 THEN Text END AS Forename,
            CASE x.StaticQuestionId WHEN 2 THEN Text END AS Surname        
        FROM     (SELECT (SELECT   link.StaticQuestionId
                          FROM     StaticQuestionQuestionLink link
                          WHERE    link.Id = qa.QuestionId
                               AND link.DateEffective <= qs.DateEffective
                               AND link.StaticQuestionId IN (1, 2)
                          ORDER BY link.DateEffective DESC LIMIT 1) AS StaticQuestionId,
                         a.Text,
                         qa.QuestionSetId
                  FROM   QuestionSet qs
                            INNER JOIN QuestionAnswerLink qa ON qs.Id = qa.QuestionSetId
                            INNER JOIN Answer a ON qa.AnswerId = a.Id
                  WHERE  qs.Id IN (1)) x) y

2:-工作查询，但在多组数据上出现不需要的结果

SELECT MAX(QuestionSetId) AS QuestionSetId,
       GROUP_CONCAT(Forename) AS Forename,
       GROUP_CONCAT(Surname) AS Surname
FROM   (SELECT
            x.QuestionSetId,
            CASE x.StaticQuestionId WHEN 1 THEN Text END AS Forename,
            CASE x.StaticQuestionId WHEN 2 THEN Text END AS Surname        
        FROM     (SELECT (SELECT   link.StaticQuestionId
                          FROM     StaticQuestionQuestionLink link
                          WHERE    link.Id = qa.QuestionId
                               AND link.DateEffective <= qs.DateEffective
                               AND link.StaticQuestionId IN (1, 2)
                          ORDER BY link.DateEffective DESC LIMIT 1) AS StaticQuestionId,
                         a.Text,
                         qa.QuestionSetId
                  FROM   QuestionSet qs
                            INNER JOIN QuestionAnswerLink qa ON qs.Id = qa.QuestionSetId
                            INNER JOIN Answer a ON qa.AnswerId = a.Id
                  WHERE  qs.Id IN (1, 2, 3)) x) y

3:-仅在1个字段上对多组数据进行工作查询

SELECT
    qs.Id AS QuestionSet,
    a.Text AS Answer
FROM
    QuestionSet qs
        INNER JOIN QuestionAnswerLink qalink ON qs.Id = qalink.QuestionSetId
        INNER JOIN StaticQuestionQuestionLink sqqlink ON qalink.QuestionId = sqqlink.QuestionId
        INNER JOIN Answer a ON qalink.AnswerId = a.Id
WHERE
        sqqlink.StaticQuestionId = 1 /* FirstName */
    AND sqqlink.DateEffective = 
            (SELECT DateEffective
               FROM StaticQuestionQuestionLink
              WHERE StaticQuestionId = 1 
                AND DateEffective <= qs.DateEffective
           ORDER BY DateEffective
               DESC 
              LIMIT 1)

@彼得，试试这个

SELECT
    qs.Id AS QuestionSet,
    GROUP_CONCAT(a.Text SEPARATOR ', ')  AS Answer
FROM
    QuestionSet qs
        INNER JOIN QuestionAnswerLink qalink ON qs.Id = qalink.QuestionSetId
        INNER JOIN StaticQuestionQuestionLink sqqlink ON qalink.QuestionId = sqqlink.QuestionId
        INNER JOIN Answer a ON qalink.AnswerId = a.Id
WHERE
        sqqlink.StaticQuestionId in (1,2,3) /* FirstName */
GROUP BY qs.Id;

或

或

---

从@PixelMaker和@PeteGO那里偷东西，我会把这个扔进去

SELECT qs.Id AS QuestionSetId,
       GROUP_CONCAT(a.Text order by a.id) AS Answer
FROM QuestionSet qs
JOIN QuestionAnswerLink qa ON qs.Id = qa.QuestionSetId
JOIN StaticQuestionQuestionLink link ON qa.QuestionId = link.QuestionId
JOIN Answer a ON qa.AnswerId = a.Id
WHERE link.Id = qa.QuestionId
      AND link.DateEffective <= qs.DateEffective
      AND link.StaticQuestionId IN (1, 2)
      and qs.id in (1,2,3)
GROUP BY qs.Id

最后是这个

---

这给出了期望的结果。

+1写得很好的问题，我建议您将来自SQL fiddle的查询放在这个网站上。在这种情况下，sql fiddle已关闭，我们无法访问您已经编写的查询：+谢谢你的快速回复，但我真的希望每个答案都在一个单独的专栏里。太好了，我想！我将在主解决方案上试用，谢谢。

SELECT
    qs.Id AS QuestionSet,
    a.Text AS Answer
FROM
    QuestionSet qs
        INNER JOIN QuestionAnswerLink qalink ON qs.Id = qalink.QuestionSetId
        INNER JOIN StaticQuestionQuestionLink sqqlink ON qalink.QuestionId = sqqlink.QuestionId
        INNER JOIN Answer a ON qalink.AnswerId = a.Id
WHERE
        sqqlink.StaticQuestionId = 1 /* FirstName */
    AND sqqlink.DateEffective = 
            (SELECT DateEffective
               FROM StaticQuestionQuestionLink
              WHERE StaticQuestionId = 1 
                AND DateEffective <= qs.DateEffective
           ORDER BY DateEffective
               DESC 
              LIMIT 1)

SELECT
    qs.Id AS QuestionSet,
    GROUP_CONCAT(a.Text SEPARATOR ', ')  AS Answer
FROM
    QuestionSet qs
        INNER JOIN QuestionAnswerLink qalink ON qs.Id = qalink.QuestionSetId
        INNER JOIN StaticQuestionQuestionLink sqqlink ON qalink.QuestionId = sqqlink.QuestionId
        INNER JOIN Answer a ON qalink.AnswerId = a.Id
WHERE
        sqqlink.StaticQuestionId in (1,2,3) /* FirstName */
GROUP BY qs.Id;

SELECT
    qs.Id AS QuestionSet,
    group_CONCAT(b.Text ORDER BY b.Id )   AS Answer
FROM
    QuestionSet qs
        INNER JOIN QuestionAnswerLink qalink ON qs.Id = qalink.QuestionSetId
        INNER JOIN StaticQuestionQuestionLink sqqlink ON qalink.QuestionId = sqqlink.QuestionId
        INNER JOIN Answer a ON qalink.AnswerId = a.Id
INNER JOIN Answer b ON qalink.AnswerId = b.Id
WHERE
        sqqlink.StaticQuestionId in (1,2,3)  
   group by qs.Id  ;

select qs.Id, group_concat(a.Text order by a.Id) from QuestionAnswerLink qalink
left join QuestionSet qs on qalink.QuestionSetId=qs.Id
left join Answer a on qalink.AnswerId = a.Id


 left join QuestionSet qs1 on qalink.QuestionSetId=qs1.Id
left join Answer b on qalink.AnswerId = b.Id


group by qs.Id ;

SELECT qs.Id AS QuestionSetId,
       GROUP_CONCAT(a.Text order by a.id) AS Answer
FROM QuestionSet qs
JOIN QuestionAnswerLink qa ON qs.Id = qa.QuestionSetId
JOIN StaticQuestionQuestionLink link ON qa.QuestionId = link.QuestionId
JOIN Answer a ON qa.AnswerId = a.Id
WHERE link.Id = qa.QuestionId
      AND link.DateEffective <= qs.DateEffective
      AND link.StaticQuestionId IN (1, 2)
      and qs.id in (1,2,3)
GROUP BY qs.Id

SELECT qs.Id AS QuestionSetId,
       GROUP_CONCAT(case link.staticquestionid when 1 then a.Text end) AS forename,
       GROUP_CONCAT(case link.staticquestionid when 2 then a.Text end) AS surname
FROM QuestionSet qs
JOIN QuestionAnswerLink qa ON qs.Id = qa.QuestionSetId
JOIN StaticQuestionQuestionLink link ON qa.QuestionId = link.QuestionId
JOIN Answer a ON qa.AnswerId = a.Id
WHERE link.Id = qa.QuestionId
      AND link.DateEffective <= qs.DateEffective
      AND link.StaticQuestionId IN (1, 2)
      and qs.id in (1,2,3)
GROUP BY qs.Id