Database relation one to one based on type -


i have following tables:

  • user : id, typeid ..
  • type: id, name ..

based on type user has between 1 3 values. example user 1 typ b, , type b has 3 values. type have 2 values. create different value-tables

  • valuesa: id, min-value, max-value, userid
  • valuesb: id, value1, value2, value3, userid ...

and use userid foreign key, , decide table should use based on type. or create 1 value-table value-fields , leave empty fields in rows, , add valueid users table? or better way this?

the better way normalize value rows.

value ----- user id type id sequence value

the primary key table (user id, type id, sequence). sequence column makes primary key unique. type a, sequence 1 , 2. type b, sequence 1, 2, , 3.

this design allows flexibility have 0 values, 5 values, or 150 values given user , type.


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