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1 ( s e c u r i t y ) ( i n t e g r i t y ) D B A D B M S 8

2 370 D B M S (discretionary control) ( ) U 1 A B U 2 B A (mandatory control) (classification level) (clearance level) U 1 A B B A U 2 B A D B M S D B M S a b D B M S (security subsystem) authorization subsystem I D ( p a s s w o r d ) I D I D [ ]

3 (user group) [ ] 16.2 D B M S ( a u t h o r i t y ) AUTHORITY SA3 GRANT RETRIEVE (S#,SNAME,CITY),DELETE O N S T O J i m, F r e d, M a r y ; 1) S A 3 2) R E T R I E V E D E L E T E G R A N T 3) S O N 4) I D TO AUTHORITY <authority name> GRANT <privilege commalist> ON TO <relvar name> <user ID commalist>; <authority name> <relvar name> <user ID commalist> A L L I D <p r i v i l e g e> RETRIEVE [ <attribute name commalist> ] INSERT UPDATE D E L E T E A L L [ <attribute name commalist> ] [ <attribute name commalist> ] R E T R I E V E I N S E RT U P D AT E D E L E T E Tutorial D Tutorial

4 372 R E T R I E V E R E T R I E V E I N S E RT U P D AT E A L L R E T R I E V E I N S E RT U P D AT E D E L E T E data manipulation (threat monitoring) DROP AUTHORITY <authority name>; DROP AUTHORITY SA3; 1 ) AUTHORITY EX1 GRANT RETRIEVE(P#,PNAME,WEIGHT) ON P TO Jacques,Anne,Charley; J a c q u e s A n n e C h a r l e y P 2 ) AUTHORITY EX2 GRANT RETRIEVE U P D A T E ( S N A M E, S T A T U S ) D E L E T E ON LS TO Dan, Misha; L S L o n d o n D a n M i s h a S D a n M i s h a S L S I N S E RT S # C I T Y UPDATE 3 ) VAR SSPPR VIEW S JOIN SP JOIN P WHERE CITY='Rome' { P #} AUTHORITY EX3 GRANT RETRIEVE O N S S P P R T O G i o v a n n i ; {ALL BUT P#,QTY}; R E T R I E V E

5 G i o v a n n i R o m e 4 ) VAR SSQ VIEW SUMMARIZE SP PER S{S#} ADD SUM{QTY} AS SQ AUTHORITY EX4 GRANT RETRIEVE O N S S Q T O F i d e l F i d e l 5 ) AUTHORITY EX5 GRANT RETRIEVE U P D A T E S T A T U S O N WHEN S DAY I N ' M o n ',' T u e ',' W e d ',' T h r ',' F r i ' AND NOW() TIME '09:00:00' AND NOW() TIME '17:00:00' TO Purchasing ; A U T H O R I T Y W H E N niladic operatord AYN O W E X 5 P u r c h a s i n g p u r c h a s i n g c o n t e x t - d e p e n d e n t T O D A Y ( ) U S E R ( ) T E R M I N A L ( ) I D I D a N a n c y b 1. I n g r e s Q U E L Q U E L U L o n d o n DEFINE PERMIT RETRIEVE ON P TO U W H E R E P.CITY = "London" U Q U E L R E T R I E V E ( P. P #, P. W E I G H T ) WHERE P.COLOR = "Red" P U

6 374 R E T R I E V E ( P. P #, P. W E I G H T ) W H E R E P.COLOR = "Red" A N D P.CITY = "London" U U L o n d o n [ ] I n g r e s U P R E T R I E V E P DEFINE PERMIT DEFINE PERMIT <operation name commalist> O N <relvar name>[(<attribute name commalist>)] T O <user ID> [ AT <terminal name commalist>] [ FROM <time> TO <time>] [ ON <day> TO <day> ] [ WHERE <boolean expression>] A U T H O R I T Y W H E R E DEFINE PERMIT APPEND,RETRIEVE,REPLACE O N S ( S #, C I T Y ) T O J o e AT T T A 4 FROM 9:00 TO 17:00 O N Sat TO Sun WHERE S.STATUS < 50 A N D S.S# = SP.P# A N D SP.P# = P.P# A N D P.COLOR = "Red" Q U E L A P P E N D R E P L A C E I N S E RT UPDATE 2. 14

7 c l a s s i f i c a t i o n s t r u c t u r e classification level clearence level > > B e l l La Padula[16.1] 1) i j i j 2) i j i j i I N S E RT i j i j D B M S [ ] [ ] Trusted Computing Base T C B D C B A D A D m i n i m a l C d i s c r e t i o n a r y B m a n d a t o r y A v e r i f i e d C C 1 C 2 C 1 C 2 1) C 1 2) C2 a c c o u n t a b i l i t y B B 1 B 2 B 3 B 1 B 3 1) B 1 2) B 2 f o r m a l c o v e r t

8 376 c h a n n e l a b 3) B3 A D B M S B 1 C 2 D B M S multi-level secure system [ , , ] trusted system [ , ~ ] S = 3 = 2 = 16-1 S U 1 U U 1 U 2 S U 1 S 1 S 2 S 3 S 5 U 2 S 1 S 3 U 1 U 2 S 4 request modification L o n d o n S WHERE CITY = 'London' S WHERE CITY = 'London' AND CLASS user clearance U 1 S 4 U 1 I N S E RT INSERT INTO S RELATION {TUPLE {S#S # ' S 4 ', S N A M E N A M E (' B a k e r '), STATUS 25, C I T Y ' R o m e '}}; I N S E RT S 4 INSERT INTO S RELATION {TUPLE{ S# S# ' S 4 ', SNAME NAME('Baker'), STATUS 25, CITY 'Rome', CLASS CLASS(3)}}; { S #} { S # C L A S S }

9 multi-level relvar p o l y i n s t a n t i a t i o n S 4 U P D ATE D E L E T E 16.4 [16.4] A d a m s [ ] S TAT S 16-2 U A l f U A l f STATS 1 ) W I T H STATS WHERE SEX = 'M' AND OCCUPATION = 'Programmer' AS X C O U N T X 1 2 ) W I T H STATS WHERE SEX = 'M' AND OCCUPATION = 'Programmer' AS X S U M X S A L A R Y 50 K U Tutorial D 1 COUNT (X) E X T E N D TABLE_DEE ADD COUNT(X) AS RESULT

10 378 b N-b N 3 ~ 6 3 ) C O U N T S T A T S 12 4 ) W I T H STATS WHERE NOT SEX = 'M' AND OCCUPATION = 'Programmer' AS X C O U N T X = 1 5 ) S U M S T A T S S A L A R Y 728 K 6 ) W I T H STATS WHERE NOT SEX = 'M' AND OCCUPATION = 'Programmer' AS X S U M X S A L A R Y 678 K 7 28 K 6 78 K = 50 K c b c N b 16-2 b = 2 2 c 8 SEX = 'M' AND OCCUPATION = 'Programmer' 7 ~ 10 7 ) WITH STATS WHERE SEX = 'M' AS X C O U N T X 4 8 ) W I T H STATS WHERE SEX = 'M' AND NOT C O U N T X 3 OCCUPATION = 'Programmer' AS X 7 8 U A l f A l f 9 ) W I T H STATS WHERE SEX = 'M' AS X S U M X S A L A R Y 328 K 1 0 ) W I T H STATS WHERE SEX = 'M' AND NOT S U M X S A L A R Y 278 K 3 28 K 2 78 K = 50 K OCCUPATION = 'Programmer' SEX = 'M' AND NOT OCCUPATION = 'Programmer' A l f individual tracker [ ] I B E B E B E 1 AND B E 2 B E 1

11 AND NOT B E 2 I B E 1 B E 1 AND NOT B E 2 s e t B E = set B E 1 AND B E = set B E 1 minus set B E 1 AND NOT B E BE1 AND NOT BE2 [ ] general tracker c 2b c N 2b b N/ 4 B E B b B E N b T NOT T b= 2 c 4 c 6 U A l f SEX = 'M' AND OCCUPATION = 'Programmer' U A l f B E A l f 2 ~ 4 A l f 5 ~ 7 1 T AUDITS = 0 2 T NOT T W I T H STATS WHERE AUDITS = AS 0 X C O U N T X 5 W I T H STATS WHERE NOT AUDITS = 0AS X C O U N T X = 10 T 3 B E OR T B E OR NOT T B E W I T H STATS WHERE SEX = 'M' AND OCCUPATION = 'Programmer'

12 380 C O U N T X 6 OR AUDITS = 0 AS X W I T H STATS WHERE SEX = 'M' AND OCCUPATION = 'Programmer' C O U N T X = 11 OR NOT AUDITS = 0AS X 4 B E B E A l f S U M C O U N T 5 T NOT T W I T H STATS WHERE AUDITS = AS 0 X S U M X S A L A R Y 438 K W I T H STATS WHERE NOT AUDITS = 0AS X S U M X S A L A R Y 290 K 4 38 K K = 728 K 6 B E OR T B E OR NOT T A l f W I T H STATS WHERE SEX = 'M' AND OCCUPATION = 'Programmer' S U M X S A L A R Y 488 K OR AUDITS = 0 AS X W I T H STATS WHERE SEX = 'M' AND OCCUPATION = 'Programmer' S U M X S A L A R Y OR NOT AUDITS = 0AS X 290 K 4 88 K K = 778 K A l f 50 K s e t B E = s e t B E OR T plus set B E OR NOT T minus set T OR NOT T 16-4 T T B E O R T (BE OR NOT T) B E T

13 p q p < b b q 2b (B E OR T) p+q 2b : B E T p q p < b b q 2b (B E OR NOT T) p+n q N 2b N N b N (B E OR NOT T) [ ] T 5 3 [ ] [ D e n n i n g [ ] 16.5 AS KINGFISHERS CATCH FIRE E L I O T 1) + AS+KI NGFIS HERS+ CATCH +FIRE 2) 0 0 ~ 26 = 00 A = Z = ) ) 27

14 382 5) 4 FDIZB SSOXL MQ+GT HMBRA ERRFY 1. Data Encryption Standard D E S I B M 1977 [ ] D E S i K K i Ki [16.18] D E S K i 2. D E S D E S D E S D i ff i e H e l l m a n [ ] R i v e s t S h a m i r A d l e m a n [ ] R S A 1) 2) [ ] R S A [ ] Arjen Lenstra M a r k M a n a s s e 155 [ ] ( 512 = 2 9 ) [ ] R S A

15 R S A 1) p q r=p*q 2) e e (p 1 )*(q 1 ) e p q 3) d d * e = 1 modulo p - 1 * q - 1 e p q d [ ] 4) r e d 5) P ( P r ) C C = Pe modulo r 6) C P P = C d modulo r [ ] d C P r e p q d d p=3, q= 5 r= 15p 1 * q 1 = 8 e= 11 p q d * 11 = 1 modulo 8 d = 3 13 C C = P e modulo r = 1311 modulo 15 = 1,792,160,394,037 modulo 15 = 7 P P = C d modulo r = 73 modulo 15 = 343 modulo 15 = 13 e d A B A B E C A E C B D C A D C B E C A D C A E C B D C B A B P E C B P P D C A E C B C C = ECB D C A P B C D C B E C A P E C A D C B C = ECA D C B E C B D C A P = ECA D C A P /* D C B E C B */ = P /* D C B E C B */

16 384 B A D C E C P A D C A B A 16.6 SQL S Q L S Q 1. S Q L ~ 4 S Q L 2) CREATE VIEW LS AS SELECT S.S#,S.SNAME,S.STATUS,S.CITY F R O M S W H E R E S.CITY = 'London' ; G R A N T GRANT SELECT U P D A T E S N A M E S T A T U SD E L E T E O N L S T O D a n M i s h a S Q L G R A N T C R E ATE AUTHORITY 3 ) CREATE VIEW SSPPR AS SELECT S.S#,S.SNAME,S.STATUS,S.CITY F R O M S W H E R E E X I S T S SELECT FROM P WHERE EXISTS G R A N T SELECT FROM P WHERE S.S# = SP.S# A N D SP.S# = P.P# A N D P.CITY = 'Rome' ; GRANT SELECT ON SSPPR TO Giovanni ; 4 ) CREATE VIEW SSQ AS SELECT S.S#, SELECT SUM S P. Q T Y F R O M S ; G R A N T F R O M S P WHERE SP.S# = S.S# AS SQ GRANT SELECT ON SSQ TO Fidel ; S Q L C U R R E N T _ U S E R C U R R E N T _ D AT E C U R R E N T _ T I M E S Q L 5 D AY

17 CREATE VIEW S_NINE_TO_FIVE AS SELECT S.S#,S.SNAME,S.STATUS,S.CITY F R O M S W H E R E CURRENT_TIME TIME '09:00:00' A N D CURRENT_TIME TIME '17:00:00' ; G R A N T GRANT SELECT U P D A T E S T A T U S O N S _ N I N E _ T O _ F I V E T O Purchasing ; S _ N I N E _ TO _ F I V E C U R R E N T _ U S E R S _ N I N E _ TO _ F I V E L o n d o n 2. GRANT R E V O K E G R A N T T T S E L E C T I N S E RT U P D AT E D E L E T E R E F E R E N C E S with grant authority G R A N T GRANT <privilege commlist> ON <object> TO <user ID commlist> [WITH GRANT OPTION] ; <p r i v i l e g e> U S A G E S E L E C T I N S E RT U P D AT E D E L E T E R E F E R E N C E S U S A G E S Q L R E F E R E N C E S I N S E RT U P D AT E R E F E R E N C E S S E L E C T A L L P R I V I L E G E S [ ] (PSM-Persistent Stored Module) 1996 E X E C U T E

18 386 <o b j e c t> D O M A I N <domain name> TA B L E <table name> TA B L E <user ID commalist> P U B L I C WITH GRANT OPTION W I T H GRANT OPTION G R A N T A B B R E V O K E REVOKE [GRANT OPTION FOR] <privilege commalist> ON <object> FROM <user ID commalist> <option> ; a GRANT OPTION FOR b <privilege commalist> <o b j e c t> <user ID commalist> G R A N T c <o p t i o n> R E S T R I C T C A S C A D E 1 ) REVOKE SELECT ON S FROM Jacques,Anne,Charley RESTRICT; 2 ) REVOKE SELECT,UPDATE(SNAME,STATUS),DELETE ON LS FROM Dan,Misha CASCADE; 3 ) REVOKE SELECT ON SSPPR FROM Giovanni RESTRICT; 4 ) REVOKE SELECT ON SSQ FROM Fidel RESTRICT; R E S T R I C T CASCADE: p A p B B C A B p R E V O K E C p B B p R E S T R I C T C A S C A D E R E S T R I C T R E V O K E C A S C A D E 16.7 D B M S R E T R I E V E U P D AT E I n g r e s Q U E L

19 [ ~ ], R S A S Q L G R A N T R E V O K E D B M S D B 2 D B 2 D B S TAT S S T A T S { N A M E, S E X, C H I L D R E N, O C C U P A T I O N, S A L A R Y, T A X, A U D I T S } PRIMARY KEY{NAME} a. F o r d R E T R I E V E b. S m i t h I N S E RT D E L E T E c. R E T R I E V E d. N a s h R E T R I E V E S A L A RY TA X UPDATE e. To d d N A M E S A L A RY TA X R E T R I E V E f. Wa r d R E T R I E V E To d d S A L A RY TA X U P D AT E g. P o p e p r e a c h e r h. J o n e s D E L E T E 10 i. K i n g R E T R I E V E 16.2 A U T H O R I T Y H a l h o m e m a k e r H a l t a x

20 AS KINGFISHES CATCH FIRE 5 F N W A L J P V J C F P E X E A B W N E A Y E I P S U S V D 16.6 R S A p= 7 q= 5 e= 17 P= S Q L S Q L 16.1 D. E. Bell and L.J.La Padula: Secure Computer Systems: Mathematical Foundation and M o d e l, MITRE Technical Report M74-244(May 1974) Silvana Castano,Mariagrazia Fugini,Giancarlo Martella,and Pierangela Samarati: D a t a b a s e S e c u r i t y. New Yo r k, N. Y.: ACM Press/Reading,Mass.: Addison-We s l e y ( ) James Daly: Fingerprinting a Computer Security Code, C o m p u t e rworld ( J u l y 2 7 t h, ) C. J. D a t e : S e c u r i t y, Chapter 4 of An Introduction to Database Systems:Volume II. Reading, Mass.:Addison-We s l e y ( ) Dorothy E.Denning: C ryptography and Data Security. Reading Mass.: Addison- We s l e y ( ) Dorothy E.Denning and Peter J.Denning: Data Security, ACM Comp.Surv. 11, No.3 (Septemper 1979) W. D i ffie and M.E.Hellman: New Direction in Cryptography, IEEE Transactions on Information Theory I T-22(November 1976) Ronald Fagin: On an Authorization Mechanism, ACM TODS 3.No.3(September 1978). [ ] [ ] 16.9 Roberto Gagliardi,George Lapis,and Burce Lindsay: A Flexible and Efficient Database Authorization Facility, IBM Research Report RJ6826(May 11 t h, ) Martin Gardner: A New Kind of Cipher That Would Take Millions of Years to Break, Scientific American 237, No.2(August 1977). [ , ] Patricia P. G r i ffiths and Bradford W. Wa d e : An Authorization Mechanism for a Relational Data Base System, ACM TODS 1, NO.3(September 1976).

21 System R G R A N T R E V O K E S Q L Nigel Hawkes: Breaking into the Internet, London Times (March 18th,1996). R S A Sushil Jajodia and Ravi Sandhu: Toward a Multi-Level Secure Relational Data Model, Proc.1991 ACM SIGMOD Int. Conf. on Management of Data, Denver, Colo.(June 1991) Abraham Lempel: Cryptology in Tr a n s a c t i o n, ACM Comp.Surv. 11, No.4:Special Issue on Cryptology(December 1979) R.L.Rivest, A.Shamir,and L.Adleman: A Method for Obtaining Digital Signatures and Public Key Cryptosystems, CACM 21, No.2(February 1978) Ken Smith and Marianne Wi n s l e t t : Entity Modeling in the MLS Relational Model, Proc.18th Int. Conf. on Very Large Data Bases,Va n c o u v e r,canada(angust 1992). M L S [ ] M L S BELIEVED BY [ ] Bhavani Thuraisingham: Current Status of R&D in Trusted Database Management S y s t e m, ACM SIGMOD Record 21, No.3(September 1992) U.S.Department of Commerce/National Bureau of Standands: Data Encryption Standard. Federal Information Processing Standards Publication 46(1977 January 15). D E S / U.S.Department of Defense: Trusted Computer System Evaluation Criteria (the O r a n g e B o o k ),Document No.DoD STD.DoD National Computer Security Center(December 1985) U.S.National Computer Security Center: Trusted Database Management System I n t e p retation of Trusted Computer System Evaluation Criteria ( t h e L a v e n d e r B o o k ),Document No.NCSC-TG-201,Version 1(April 1991) Marianne Winslett,Kenneth Smith,and Xiaolei Qian: Formal Query Languages for Secure Relational Databases, ACM TODS 19, No.4(December 1994). [ ]

22 Ron Wo l f : How Safe Is Computer Data?A Lot of Factors Govern the Answer, San Jose M e rc u ry News (July 5th,1990) a. AUTHORITY AAA GRANT RETRIEVE ON STATS TO Ford ; b. AUTHORITY BBB GRANT INSERT,DELETE ON STATS TO Smith ; c. AUTHORITY CCC GRANT RETRIEVE O N S T A T S WHEN USER() = NAME T O ALL ; I D W H E N U S E R d. AUTHORITY DDD GRANT RETRIEVE,UPDATE(SALARY,TAX) O N S T A T S T O Nash ; e. AUTHORITY EEE GRANT RETRIEVE(NAME,SALARY,TAX) ON STATS TO Todd ; f. AUTHORITY FFF GRANT RETRIEVE(NAME,SALARY,TAX), U P D A T E ( S A L A R Y, T A X ) O N S T A T S T O Ward ; g. VAR PREACHERS VIEW STATS WHERE OCCUPATION = 'Preacher' ; AUTHORITY GGG GRANT ALL ON PREACHERS TO Pope ; h. VAR NONSPECIALIST VIEW WITH (STATS RENAME OCCUPATION AS X) AS T1, (EXTEND STATS ADD COUNT (T1 WHERE X = OCCUPATION) AS Y) AS T2, (T2 WHERE Y > 10) AS T3: T3 {ALL BUT Y} AUTHORITY HHH GRANT DELETE

23 ON NONSPECIALIST TO Jones ; i. VAR JOBMAXMIN VIEW WITH(STATS RENAME OCCUPATION AS X) AS T1, (EXTEND STATS ADD MAX(T1 WHERE X = OCCUPATION,SALARY) AS MAXSAL, MIN(T1 WHERE X = OCCUPATION,SALARY) AS MINSAL) AS T2: T 2 { O C C U P A T I O N, M A X S A L, M I N S A L } AUTHORITY III GRANT RETRIEVE ON JOBMAXMIN TO King ; 16.2 S Q L R E T R I E V E I N S E RT U P D AT E D E L E T E 16.3 Hal CHILDREN > 1 AND NOT OCCUPATION = 'Homemaker' C O U N T STATS WHERE CHILDREN > 1 6 C O U N T STATS WHERE CHILDREN > 1 AND NOT 5 OCCUPATION = 'Homemaker' CHILDREN > 1 AND NOT OCCUPATION = 'Homemaker' H a l S U M STATS WHERE CHILDREN > T 1A X 48 K S U M STATS WHERE CHILDREN > 1 AND NOT 46 K H a l t a x 2 K 16.4 SEX = 'F' OCCUPATION = 'Homemaker' T A X S U M STATS WHERE SEX = 'F' T A X 70 K S U M STATS WHERE NOT SEX = 'F'T A X 16 K t a x 8 6 K S U M STATS WHERE CHILDREN > 1 AND OCCUPATION = 'Homemaker' OR SEX = 'F' T A X

24 K S U M STATS WHERE CHILDREN > 1 AND OCCUPATION = 'Homemaker' OR NOT SEX = 'F' T A X 16 K H a l t a x 88 K - 86 K = 2 K 16.5 EYES I DARE NOT MEET IN DREAMS a. GRANT SELECT ON STATS TO Ford ; b. GRANT INSERT,DELETE ON STATS TO Smith ; c. CREATE VIEW MINE AS SELECT STATS.* FROM STATS WHERE STATS.NAME = CURRENT_USER ; GRANT SELECT ON MINE TO PUBLIC ; I D C U R R E N T _ U S E R d. GRANT SELECT,UPDATE(SALARY,TAX) ON STATS TO Nash ; e. CREATE VIEW UST AS SELECT STATS.NAME,STATS.SALARY,STATS.TAX FROM STATS ; GRANT SELECT ON UST TO Todd ; S Q L S E L E C T f. GRANT SELECT,UPDATE(SALARY,TAX) ON UST TO Ward ; g. CREATE VIEW PREACHERS AS SELECT STATS.* FROM STATS WHERE STATS.OCCUPATION = 'Preacher' ; GRANT ALL PRIVILEGES ON PREACHERS TO Pope ; ALL PRIVILEGES ALL PRIVILEGES G R A N T h. CREATE VIEW NONSPECIALIST AS SELECT STX.* FROM STATS AS STX WHERE (SELECT COUNT(*) FROM STATS AS STY

25 WHERE STY.OCCUPATION = STX.OCCUPATION) >10 ; GRANT DELETE ON SPECIALISTS TO Jones ; i. CREATE VIEW JOBMAXMIN AS SELECT STATS.OCCUPATION, MAX(STATS.SALARY) AS MAXSAL, MIN(STATS.SALARY) AS MINSAL FROM STATS GROUP BY STATS.OCCUPATION ; GRANT SELECT ON JOBMAXMIN TO King ; a. REVOKE SELECT ON STATS FROM Ford RESTRICT ; b. REVOKE INSERT,DELETE ON STATS FROM Smith RESTRICT ; c. REVOKE SELECT ON MINE FROM PUBLIC RESTRICT ; d. REVOKE SELECT,UPDATE(SALARY,TAX) ON STATS FROM Nash RESTRICT ; e. REVOKE SELECT ON UST FROM Todd RESTRICT ; f. REVOKE SELECT,UPDATE(SALARY,TAX) ON UST FROM Ward RESTRICT ; g. REVOKE ALL PRIVILEGES ON PREACHERS FROM Pope RESTRICT ; h. REVOKE DELETE ON NONSPECIALIST FROM Jones RESTRICT i. REVOKE ON SALS FROM King RESTRICT

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ebook 165-5 3 5 6 7 8 9 [ 3. 3 ] 3. 3 S Q L S Q 4. 21 S Q L S Q L 4 S Q 5 5.1 3 ( ) 78 5-1 3-8 - r e l a t i o n t u p l e c a r d i n a l i t y a t t r i b u t e d e g r e e d o m a i n primary key 5-1 3 5-1 S #