Anomalies Consider the following tablethat keeps track of BOTH graduate students

Question

Anomalies Consider the following tablethat keeps track of BOTH graduate students as well as professors. Then solve problems 1-4. adIn rad_fn proffn rof In profphone Frank Nora Nerd 928-523-9999 e teen Steve Supersmart 928-523-1111 Nick Grandiose Nora Nerd 928-523-9999 Goofy Faulpelz Nichtsnutz | 1. Show how an insertion anomaly may happen. (1pt) 2. Show how an update anomaly may happen. (1 pt) 3. Show how a delete anomaly may occur. (1 pt) 4. Which parts of the above table contain redundancies? (1pt)

Explanation / Answer

1)

An insert anomaly occurs when certain attributes cannot be inserted into the database without the presence of other attributes.

In the given table we cannot add a professor without having a student detail who is taught by the professor or vice versa.

2)

An update anomaly exists when one or more instances of duplicate data is updated, but not all.

In the given table consider Professor Nora phone number change request, we need to update all instances of Professor Nora’s phone.

3)

A delete anomaly happens when certain attributes are lost on deletion of some other attributes.

In the given table if a professor (prof_fn = Steve) is deleted the corresponding graduate (grad_fn = Nick) detail will also be deleted.

4)

In the given table two different students belongs or taught by Professor Nora Nerd. For keeping the details of these two students (Frank and Goofy), information related to professor Nora like first name, last name and phone are inserted twice, which is a redundant data.

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.