Database Management
Autor: Zhu Ying • October 18, 2016 • Lab Report • 277 Words (2 Pages) • 896 Views
You have recently been hired as a data base expert for a consulting organization. As one of your first assignments, you have been asked to redesign an existing database that captures data on the different projects under way, the employees who are assigned to each project, their job titles and hourly charge rates, and the number of hours they have devoted to each project. The users are not happy with the existing database for several reasons.
This database was implemented by another employee as an Access data base. The corresponding table is reproduced below. This person was unable to set a primary key because of the nature of the database, and felt it is a shortcoming of MS Access. The individual who maintains the data feels that she is often duplicating information when adding new rows of data.
- Is the shown table in first normal form? If not, how could you convert it to such a table?
- Infer the functional dependencies across the different attributes based on the description above and the data shown.
- Identify instances of insertion, deletion, and modification anomaly if they exist.
- Convert the relation to a set of 3NF relations. Give reasons for your answer.
- Are the relations proposed in part (d) in BCNF? Why or why not?
PROJECTS
Proj# | Proj_Name | Emp# | Emp_Name | Job_Title | Rate | Hours |
15 | Evergreen | 103 | June E. Arbough | Elect. Engineer | $84.50 | 23.80 |
101 | John G. News | Database Designer | $105.00 | 19.40 | ||
105 | Alice K. Johnson | Database Designer | $105.00 | 35.70 | ||
106 | William Smithfield | Programmer | $35.75 | 12.60 | ||
102 | David H. Senior | Systems Analyst | $96.75 | 23.80 | ||
18 | Amber Wave | 114 | Annelise Jones | Applications Designer | $48.10 | 24.60 |
118 | James J. Frommer | General Support | $18.36 | 45.30 | ||
104 | Anne K. Ramoras | Systems Analyst | $96.75 | 32.40 | ||
112 | Darlene M. Smithson | DSS Analyst | $45.95 | 44.00 | ||
22 | Rolling Tide | 105 | Alice K. Johnson | Database Designer | $105.00 | 64.70 |
104 | Anne K. Ramoras | Systems Analyst | $96.75 | 48.40 | ||
113 | Delbert K. Joenbrood | Applications Designer | $48.10 | 23.60 | ||
111 | Geoff B. Wabash | Clerical Support | $26.87 | 22.00 | ||
106 | William Smithfield | Programmer | $35.75 | 12.80 | ||
25 | Starflight | 107 | Maria D. Alonzo | Programmer | $35.75 | 24.60 |
115 | Travis B. Bawangi | Systems Analyst | $96.75 | 45.80 | ||
101 | John G. News | Database Designer | $105.00 | 56.30 | ||
114 | Annelise Jones | Applications Designer | $48.10 | 33.10 | ||
108 | Ralph B. Washington | Systems Analyst | $96.75 | 23.60 | ||
118 | James J. Frommer | General Support | $18.36 | 30.50 | ||
112 | Darlene M. Smithson | DSS Analyst | $45.95 | 41.40 |
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