실습1_ERD

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Unformatted text preview: * Æ g + 1 . 2. ø f + “ * P ( „ �� @ W f + U „ „ “ * ( � @ f + W ) DBMS � � DBMS � � @ W f + (� � � ) H “ * (� � � � � � „ � @ n + W ) � @ f + W 11/04/09 2 F 11/04/09 3 @ W f + s s (1) s H 9 n  , � , � @ n f W � � � ¤ (DEPARTMENT) ( „ “ . � ¤ (name), � (number), ( Z „ * � � . � � � � � � ¤ (start date) ( Z „ “ * . � , H 9 “ * � (location) � � � � � � A n f + „ “ Ł j. � W n e � (PROJECT) H 9 „“ * � . ( Z „“ * � (name) � � (number) � � �� � ¤ (location) � � . 11/04/09 4 @ W f + s (2) s � � (EMPLOYEE) „ “ *� � (social security number), (address), � (salary), � (sex), � (Name) h •“ * . W nf � ‘ § • * Ł(works for) � @ n f + � � � � � � (work on). � � � � � @ « ¥ E 7 . � , � � � � � (direct supervisor) „ “ * . � W n � � � � � � � � (DEPENDENT) 9 „ “ * . h • “ e 9 „ “ �� (name), � (sex), h § • * � (relationship) �� . 11/04/09 5 8 ª * 11/04/09 6 ER � s s s Entity � � � 7 @ @ @ @ ¥ E ( ł7 “ * @@ @ « E & j f p « E + ¥ A W n e+ — • “ Ł K „ @ « ¥ @ E ’ j + p «E A n e + — • * Ł ER � @W e + s 11/04/09 7 ER ¨ Z s ª * 7 � �� x x x @ « ¥ & j f + p ¥ E EMPLOYEE, � DEPARTMENT, ProductX PROJECT u ��� e +� “ ¥ E EMPLOYEE ¨ Z „ Name, SSN, Address, Sex, Salary �� � � � � « ¥ E � � � � � � � � @ � � � Wn f � � � � � Name=‘ � � ', SSN='123456789', Address =‘ � � � � � � ', Sex=‘ ‘ 11/04/09 8 3ÐO ¹ª s x @ @ Sex (1) « ¥ E % j + p « E . ł ; ¹ n * s ł ; „ n  x s ł; „ n * � � x �� « ¥ Address ( , , , � ) Name (FirstName, LastName) �@ W n + � � � �� � � . s ł; „ n * � x t � e + � “ ¥ E� � � � � � �� @ « {Location} � � � � � � 9 11/04/09 87 ¹ª s X Birth_date Age (2) � �� x s �� � � � � X x s � x x (NULL) � �� � @ ¥ E ¥ E 7 @ « �� e + 11/04/09 10 ø= ¹ª s x � � �� (3) 7 SSN @ « @ @ « ¥ E ! 8 „ n EMPLOYEE x e + � ¥ PROJECT s s NAME, NUMBER Łj „ n * �Æı g f + « f + 87 „ n WORKS_ON Hours A W f + 7 “ * Ł � EMPLOYEE PROJECT Wn +� = „ “ * Ł j 11/04/09 11 s ˜ ProductX PROJECT 8 Z „ * � � , * � DEPARTMENT � � @@ x s � � x EMPLOYEE 8 Z „ EMPLOYEE 6„ @ « E j f + p ¥ E s “� � e + � � “ E x EMPLOYEE � PROJECT 8 „ “ *� WORKS_ON 6 „ “ , EMPLOYEE � DEPARTMENT 8 „ “* � MANAGES � � MANAGES WORKS_ON � �� � � �� @« E� �� @ @ « ¥ 11/04/09 12 @ n f + s x @ W e + ¨4 x s � x „ n 1:1, 1:N, N:1, or M:N Ł j K ª * �Æ ı g f + � � �� f ¤ 4 „ n * ( � � � x „ ) (� � x ) ( 6 „ ª � � f + �� ¥ E � � � �� � � @ « E � �� � @ @ MANAGES EMPLOYEE DEPARTMENT � WORKS_FOR 11/04/09 13 @ n f + s % + p « ¥ @ x x s x 5 n * x WORK_FOR ¨8 „ “ * � EMPLOYEE � � � � � , DEPARTMENT � � � � � , � 7 @ « ¥ @ « ¥ 11/04/09 14 14 s s ˜ + p « ¥ s W n e + @ @ « E 4 ˜ A W n e p „ “ x x j K „ f @ n e + è j ¹ n * Æ ı g f + s @ n e + / x s DEPENDENT �� � � �� �@ « E 7 @ Łj K „ *� � ı f + u DEPENDENT EMPLOYEE W n + � � 5 „ “ DEPENDENT_OF Ł K „ *� �Æ g f + f � 11/04/09 15 ERD Fname Name Lname address SSn sex salary (1,1) WORKS_FOR MANAGES Start_date WORKS_ON (0,M) DEPENDENTS_OF Hours (1,M) (4,M) (1,1) Number Name Locations EMPLOYEE (1,M) (0,M) Supervisee Supervisor (0,1) SUPERVISION (0,1) DEPARTMENT (0,M) CONTROLS (1,1) PROJECT (1,1) DEPENDENT Number Name Location Name Relationship 11/04/09 Sex 16 ...
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