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Assignment 5-1 Functional Dependencies Attributes within one table True for all table instances Part of table schema (Assumptions) Cannot get FDs just.

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Presentation on theme: "Assignment 5-1 Functional Dependencies Attributes within one table True for all table instances Part of table schema (Assumptions) Cannot get FDs just."— Presentation transcript:

1 Assignment 5-1 Functional Dependencies Attributes within one table True for all table instances Part of table schema (Assumptions) Cannot get FDs just from one table instance Not normalization yet

2 Assumptions NIN, hNo, and ContractNo are unique for Staff, Hotel, and Contract, respectively. hLoc is the city where a hotel is located. Several hotels may be in the same city. One hotel could have several contracts. One contract is for one hotel. Several staff may work on one contract. One staff may work on several contracts on the same hotel. hours is the total hours of one staff on one contract. More than one employee could have the same name.

3 eName  NIN NIN contractNo hours eName hNo hLoc 1135 C1024 16 Smith J H25 East Kilbride 1135 C1025 15 Smith J H4 Glasgow ….. ……... ……… …. ……………. 1160 C1024 16 Smith J H25 East Kilbride Incorrect: eName  NIN (More than one employee could have the same name.) Correct: NIN  eName (NIN is unique for Staff)

4 NIN  All NIN contractNo hours eName hNo hLoc 1135 C1024 16 Smith J H25 East Kilbride 1135 C1025 15 Smith J H4 Glasgow ….. ……... ……… …. ……………. 1160 C1024 16 Smith J H25 East Kilbride Incorrect: NIN  All Incorrect: NIN  hours Incorrect: NIN  hNo (One staff may work on several contracts on the same hotel)

5 NIN, hNo  All NIN contractNo hours eName hNo hLoc 1135 C1024 16 Smith J H25 East Kilbride 1135 C1025 15 Smith J H4 Glasgow ….. ……... ……… …. ……………. 1135 C1029 6 Smith J H25 East Kilbride Incorrect: NIN, hNo  All (One staff may work on several contracts on the same hotel) Incorrect: NIN, hLoc  All

6 ContractNo, hNo  All NIN contractNo hours eName hNo hLoc 1135 C1024 16 Smith J H25 East Kilbride 1057 C1024 24 Hocine D H25 East Kilbride 1068 C1025 28 White T H4 Glasgow 1135 C1025 15 Smith J H4 Glasgow ….. ……... ……… …. ……………. Incorrect: ContractNo, hNo  All (Several staff may work on one contract) hNo not needed anyway: ContractNo  All Incorrect: ContractNo, hLoc  All

7 ContractNo  eName NIN contractNo hours eName hNo hLoc 1135 C1024 16 Smith J H25 East Kilbride 1057 C1024 24 Hocine D H25 East Kilbride 1068 C1025 28 White T H4 Glasgow 1135 C1025 15 Smith J H4 Glasgow ….. ……... ……… …. ……………. Incorrect: ContractNo  eName (Several staff may work on one contract) Incorrect: ContractNo  hours

8 hNo  ContractNo NIN contractNo hours eName hNo hLoc 1135 C1024 16 Smith J H25 East Kilbride 1057 C1024 24 Hocine D H25 East Kilbride 1068 C1025 28 White T H4 Glasgow 1135 C1025 15 Smith J H4 Glasgow ….. ……... ……… …. ……………. 1135 C1035 5 Smith J H4 Glasgow Incorrect: hNo  ContractNo (One hotel could have several contracts)

9 hLoc  hNo NIN contractNo hours eName hNo hLoc 1135 C1024 16 Smith J H25 East Kilbride 1057 C1024 24 Hocine D H25 East Kilbride 1068 C1025 28 White T H4 Glasgow 1135 C1025 15 Smith J H4 Glasgow ….. ……... ……… …. ……………. 1135 C1035 5 Smith J H14 Glasgow Incorrect: hLoc  hNo (hLoc is the city where a hotel is located) (Several hotels may be in the same city)

10 NIN  eName contractNo  hNo hNo  hLoc NIN, contractNo  hours NIN, contractNo  hours, eName, hNo, hLoc NIN, contractNo  All

11 1.Assumptions 2.Identify all non-trivial FDs NIN  eName contractNo  hNo hNo  hLoc NIN, contractNo  hours ( NIN, contractNo  All) 3.Choose a PK: NIN, contractNo 4.List all AKs: NONE

12 Assignment 6-1 Schedule(staffNo, dentistName, patNo, patName, surgeryNo, Date, Time) Make assumptions: staffNo, patNo, and surgeryNo are unique. (for what?) SurgeryNo is the surgery room number. Date and Time are two different attributes. No Appointment! A patient is allowed to have more than one surgery a day. Only one surgery can take place in a room at any given time. A dentist can perform only one surgery at any given time. A dentist is allocated in one surgery room each day. But a surgery room can be used by multiple dentists on the same day. Due Monday 12


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