You are asked to design and manage a database system for acompany’s human resource. There needs to be a table called WORKONthat records the many-to-many relationship set “works_on” betweenthe “emplyees” enitity set and the “projects” entity set. Thedatabase is created from an E-R diagram. To prevent someone fromentering erroneous data into the database, you want to enforce thefact that the employees specified in WORKON are indeed employees ofthe company, and the projects specified in WORKON are also valid(assuming there are separately two tables one describing theemployees, the other describing the projects). What’s the best(most efficient) way to enforce this?
A.
Using foreign key constraints.
B.
Creating one or two assertions.
C.
Defining primary keys and displaying warnings before users inputdata.
D.
Requiring users to use JDBC or ODBC.
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Answer to You are asked to design and manage a database system for a company’s human resource. There needs to be a table called WO…