sql - Primary Key in three tables -


just curious if can have same primary key in 3 different tables? going create employee, fulltime , parttime tables. make employeeid primary key 3. thoughts?

you can have primary key employeeid in table called employees. have common information, such date of hire , on.

then, each of subtables can have employeeid both primary key in table and foreign key reference employees.employeeid. 1 way implement one-of relationship using relational tables.

unfortunately, unless use triggers, mechanism doesn't prevent 1 employee being in 2 other tables, not part of question.


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