MySQL:pilih, kelompokkan, dan ubah baris menjadi kolom terpisah :)

Data Anda agak sulit ditangani.

Untuk membuat tabel pivot kolom harus unik, terlebih lagi, sehingga lima kis juga bisa muncul.

Ini cukup jelek dan berfungsi dengan myslq 5.7

Skema (MySQL v5.7)

CREATE TABLE employees (
  `id` INTEGER,
  `emp` VARCHAR(5)
);

INSERT INTO employees
  (`id`, `emp`)
VALUES
  ('1', 'emp-A'),
  ('2', 'emp-B'),
  ('3', 'emp-C');

CREATE TABLE relatives (
  `id` INTEGER,
  `emp_id` INTEGER,
  `relation` VARCHAR(6),
  `relative` VARCHAR(8),
  `birthdate` DATE
);

INSERT INTO relatives
  (`id`, `emp_id`, `relation`, `relative`, `birthdate`)
VALUES
  ('1', '1', 'spouse', 'spouse-A', '1970-01-01'),
  ('2', '1', 'kid', 'kid-A1', '1971-01-02'),
  ('3', '1', 'kid', 'kid-A2', '1972-01-01'),
  ('4', '1', 'kid', 'kid-A3', '1973-01-01'),
  ('5', '2', 'spouse', 'spouse-B', '1980-02-01'),
  ('6', '2', 'kid', 'kid-B1', '1981-02-01'),
  ('7', '2', 'kid', 'kid-B2', '1982-02-01'),
  ('8', '3', 'kid', 'kid-C1', '1991-03-01'),
  ('9', '3', 'kid', 'kid-C2', '1992-03-01');

Kueri #1

SELECT
  GROUP_CONCAT(DISTINCT
    CONCAT(
      'MAX(case when `relation` = "',
     `relation`,
      '" then `relation` end) AS `',
      relation, '`',
      ',MAX(case when `relation` = "',
     `relation`,
      '" then `birthdate` end) AS `',
      'birthdate_',relation, '`'      
    )
    ORDER BY rownumber
  ) INTO @sql
FROM
  (SELECT 
    `relation`
    ,rownumber
FROM 
    employees e
    INNER JOIN 
    (SELECT
    IF(`relation` = 'kid',IF (@empid = `emp_id`,@rn:= @rn+1,@rn:= 1),IF (@empid = `emp_id`,@rn:= @rn,@rn:= 0)) rownumber
     ,IF(`relation` = 'kid',CONCAT(`relation`,@rn),`relation`) relation
    , `relative`
    , `birthdate`
    ,@empid := `emp_id` emp_id
FROM
    (SELECT 
        * 
    FROM 
        relatives
    ORDER BY `emp_id`,FIELD(`relation`,"spouse","kid"),`birthdate`) rel
    ,(SELECT @empid := 0) a1
    ,(SELECT @rn := 0) a2) r ON e.id = r.emp_id) t1
    ;

SET @sql = CONCAT("SELECT MIN(`emp`), ", @sql, " 
                  FROM   (SELECT 
                            `emp_id`,
                            `emp` ,
                            `relation`
                            ,rownumber
                            , `relative`
                            , `birthdate`
                        FROM 
                            employees e
                            INNER JOIN 
                            (SELECT
                            IF(`relation` = 'kid',IF (@empid = `emp_id`,@rn:= @rn+1,@rn:= 1),IF (@empid = `emp_id`,@rn:= @rn,@rn:= 0)) rownumber
                             ,IF(`relation` = 'kid',CONCAT(`relation`,@rn),`relation`) 'relation'
                            , `relative`
                            , `birthdate`
                            ,@empid := `emp_id` 'emp_id'
                        FROM
                            (SELECT 
                                * 
                            FROM 
                                relatives
                            ORDER BY `emp_id`,FIELD(`relation`,'spouse','kid'),`birthdate`) rel
                            ,(SELECT @empid := 0) a1
                            ,(SELECT @rn := 0) a2) r ON e.id = r.emp_id) t1 
                   GROUP BY `emp_id`");
PREPARE stmt FROM @sql;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;

| MIN(`emp`) | spouse | birthdate_spouse | kid1 | birthdate_kid1 | kid2 | birthdate_kid2 | kid3 | birthdate_kid3 |
| ---------- | ------ | ---------------- | ---- | -------------- | ---- | -------------- | ---- | -------------- |
| emp-A      | spouse | 1970-01-01       | kid1 | 1971-01-02     | kid2 | 1972-01-01     | kid3 | 1973-01-01     |
| emp-B      | spouse | 1980-02-01       | kid1 | 1981-02-01     | kid2 | 1982-02-01     |      |                |
| emp-C      |        |                  | kid1 | 1991-03-01     | kid2 | 1992-03-01     |      |                |

Lihat di DB Fiddle