hw2 110590049
tags db database
1.
The doctor could also be a patient. Additionally, the pharmacy can sell drugs from pharmaceutical companies at different prices compared to other pharmacies.
The key icon stands for primary key. On the other side of the connection with the primary key is the foreign key.
2.
The key icon stands for primary key. On the other side of the connection with the primary key is the foreign key.
3.
3.a
有違反 Semantic Integrity Constraints，Robert 的上司是 James(888665555) ，但 Robert 的薪水(58000)比上司(55000)還高 No integrity constraints are violated.
3.b
The DEPT_LOCATIONS number should be 5, but this operation inserts 2 into it, resulting in inconsistency in the DEPT_LOCATIONS number.
3.c
No integrity constraints are violated.
3.d
Delete the PROJECT “ProductX” from the PROJECT table, and also delete the tuple from the WORKS_ON table where “Pno” is “1.”
3.e
No integrity constraints are violated.
3.f
If you modify the Pnumber from 30 to 40, you also need to change the row in the WORKS_ON table where Pno is 30 to 40. This will result in inconsistency within the WORKS_ON table.