Database Design eXercises #4
Further Constraints (some solutions)
1.
- definitely splittable
- probably unsplittable
- definitely splittable
- definitely splittable
- definitely unsplittable
- definitely splittable
2.
(a)
(b)
(c)
(d)
(e)
flattened form
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nested solution
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(f)
(g) probably ok
(h) definitely ok
(i)
(j)
3.
[Course(coursecode) offered in Year(adcode)] = offering
offering had enrollment of Tally(studentcount)
offering was lectured by Lecturer(lecturername)
offering in Rating(ratingcode) had Tally(studentcount)
offering in Rating(ratingcode) had Percent(%) *derived
schema is trivial
4.
PostalCategory(categorycode)'B' has lower limit of Weight(kg)1
PostalCategory(categorycode) has upperlimit of Weight(kg)
PostalCategory(categorycode) sent to Zone(zonenum) costs Money(dollars)
Country(countryname) belongs to Zone(zonenum)
5. invent codes for employee, department, project, label types for them,
then chart their relationships
6. ... more to come (hopefully)
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