mysql - Is it okay to reference the primary keys of all tables in database as a foreign key of one table? -

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i trying make demo database have tables 

household(primary key - hid) people(primary key - pepid) parchildold(primary key - pcoid) job(primary key - empid) school(primary key - schlid) pension(primary key - penid)

now have various attributes details of people in each household in different tables.

can take primary keys of tables , make 1 table, allkeys , reference them foreign keys in particular table?

ie: 

allkeys table primary key: akid -- other columns include  foreign keys- hid,pepid,pcoid,empid,schid,penid*

i don't know if silly ask or not, but,

is such reference allowed? can considered normalized form? queries fired in way joining allkeys table , other table(depending on query) work efficiently?

you if of tables related, fail third , fourth normal forms, having both functional , multivalued dependencies in table.

consider huge amounts of duplication required store relationships single household: 1 household (hid=1), 2 parents (pepid=1,2), 2 children (pepid=3,4), 4 parent-child relationships (pcoid=1,2,3,4), 2 jobs (empid=1,2), 1 school both children (schlid=1) , 2 pensions (penid=1,2).

akid | hid | pepid | pcoid | empid | schlid | penid -----|-----|-------|-------|-------|--------|------ 1    | 1   | 1     | 1     | 1     | null   | 1 2    | 1   | 1     | 2     | 1     | null   | 1 3    | 1   | 2     | 3     | 2     | null   | 2 4    | 1   | 2     | 4     | 2     | null   | 2 5    | 1   | 3     | 1     | null  | 1      | null 6    | 1   | 3     | 2     | null  | 1      | null 7    | 1   | 4     | 3     | null  | 1      | null 8    | 1   | 4     | 4     | null  | 1      | null

another problem that, assuming table parchildold contains parent , child column, have no way of specifying whether pcoid reference in allkeys, whether pepid refers parent or child.

in short, don't it.


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