Consider the following relational instances of EMPLOYEE andCHILDREN tables with primary keys underlined and foreign key shownby arrow. Assume the foreign key EmpID in CHILDRENtable has "on update cascade" and "on delete cascade"constraint.
Explain what constraints, if any are violated when one attemptsthe following operations: (a-e are not applied sequentially,they operate on the original instance of database shownabove. Assume domain constraints are not violated. Also,if there is no violation, explain the effect of the operation.
(a) change the EmpID 'DV001' into 'DV005' in the relationEmployee;
(b) insert <'SA002', 'M. Owen', 'Accounting','Eastside'> into table Employee;
(c) insert <null, 'DV001',5,F> into relationChildren;
(d) delete B. Giggs (DV002) from the relation Employee.
(e) insert <'SA003', null, 'Sales0Y','Eastside'> into table Employee;
Consider the following relational instances of EMPLOYEE and CHILDREN tables with primary keys underlined and foreign key
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