如何用1条记录存储家庭关系信息

Ulp*_*hat 6 sql database table-structure

让我们考虑,我们有人称.人˚F是他的父亲,人中号是他的母亲,人是他的哥哥和人的小号是他的儿子.每个人可能有很多关系.这就是为什么,我们必须创建如下的新关系表:

+----+------+
| id | name |
+----+------+
| 1  | A    |
| 2  | F    |
| 3  | M    |
| 4  | B    |
| 5  | S    |
+----+------+
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关系类型

+----+---------+
| id | value   |
+----+---------+
| 1  | Father  |
| 2  | Mother  |
| 3  | Brother |
| 4  | Son     |
| 5  | Wife    |
| 6  | Husband |
+----+---------+
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关系

+----+----------+------------+------+
| id | PersonID | RelativeID | Type |
+----+----------+------------+------+
| 1  | 1        | 2          | 1    |
| 2  | 1        | 3          | 2    |
| 3  | 1        | 4          | 3    |
| 4  | 1        | 5          | 4    |
| 5  | 2        | 1          | 4    |
| 6  | 2        | 3          | 5    |
| 7  | 3        | 1          | 4    |
| ......                            |
+----+----------+------------+------+
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在这种情况下,第一行表示2 is father of 1(对于ID)和第五行表示1 is son of 2.在现实世界中,这两行是等价的,但是如果我不插入其中一行,我就不能错过使用现有行的行.

问题是:如何制作结构,其中包含1行中的这两个含义?

Nul*_*ull 3

事实上,在 2 个亲戚之间我们有2 个关系

Person A is person B`s wife <=> Person B is person A`s husband
Person C is person D`s sister <=>Person D is person C`s brother (D is male)
Etc...
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因此,如果您为第三个表(关系)提供Reverse_Relation_Type列,那么您的问题将得到解决,并且您将不会有多余的数据,您将拥有:

+----+----------+------------+---------------+-----------------------+
| id | PersonID | RelativeID | Relation_Type | Reverse_Relation_Type |
+----+----------+------------+---------------+-----------------------+
| 1  | 1        | 2          | 1             |4                      |
| 2  | 1        | 3          | 2             |4                      |
| 3  | 1        | 4          | 3             |3                      |
| 4  | 1        | 5          | 4             |6                      |
| 6  | 2        | 3          | 5             |1                      |
| ......                                                             |
+----+----------+------------+---------------+-----------------------+
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