Instructions: Zero mark will be given if you try to bypass the SafeAssign (e.g.

Instructions: Zero mark will be given if you try to bypass the SafeAssign (e.g. misspell words, remove spaces between words, hide characters, use different character sets, convert text into image or languages other than English or any kind of manipulation).
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Question One:
Based on your understanding of specialization and generalization constraints, use your own words to define and discuss the two primary constraints: Disjointness Constraint and Completeness Constraint.
Question Two
Show the schema mapping of the following Payment EER schema diagram, using Option 8A: Multiple relations-Superclass and subclasses.
Question Three
SQL constraints are used to specify rules for the data in a table. From what has been studied, what is the benefit of using constraints in DB. Also, explain three common SQL constraint.
Question Four
Using therelational algebra operations, write the following queries on the COMPANY relational database schema shown in the figure below.
(a) Retrieve the address of employees in department 2 who work less than 5 hours per week on the ‘ProductX’ project. (b) Retrieve the names and salary of employees who work one very project.