An Introduction to Database Systems 8Ed - C J Date - Solutions Manual Episode 2 Part 4 ppsx

... into internal form 2. Convert to canonical form 3. Choose candidate low-level procedures 4. Generate query plans and choose the cheapest In practice, Stage 1 effectively becomes "convert ... different access paths to be deployed (physical data independence). Commercial optimizers do a Copyright (c) 20 03 C. J. Date page 18 .2 reasonably good job on the second aspect...

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... suppliers-and-parts database: CREATE TYPE S# AS CHAR(5) FINAL ; CREATE TYPE P# AS CHAR(6) FINAL ; CREATE TYPE J# AS CHAR (4) FINAL ; CREATE TYPE NAME AS CHAR (20 ) FINAL ; CREATE TYPE COLOR AS CHAR( 12) ... point that is the center of circle c */ a. OPERATOR DIAMETER ( C CIRCLE ) RETURNS LENGTH ; RETURN ( 2 * THE_R ( C ) ) ; END OPERATOR ; OPERATOR CIRCUMFERENCE ( C...

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... projections──though as we know, this objective and the objective of decomposing to 5NF, or even just to BCNF, can unfortunately be in conflict.) Copyright (c) 20 03 C. J. Date page 12. 15 ... 13 .2 MVDs and 4NF Mostly self-explanatory. Possible points for the instructor to note: Copyright (c) 20 03 C. J. Date page 12. 19 12. 7 NADDR is in 2NF but not 3NF...

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... SPJ { S#, P# } JOIN SPJ { P#, J# } JOIN SPJ { J# , S# } ; Calculus version: CONSTRAINT SPJ_JD SPJ = { SPJX.S#, SPJY.P#, SPJZ .J# } WHERE SPJX.P# = SPJY.P# AND SPJY .J# = SPJZ .J# AND SPJZ.S# ... CTXD1.COURSE = CTXD2.COURSE AND CTXD1.TEACHER = CTXD2.TEACHER AND CTXD1.TEXT = CTXD2.TEXT ) AND ( NOT EXISTS ( SELECT DISTINCT COURSE, TEACHER, TEXT FROM ( ( SELECT DISTINCT COURSE,...

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... T1-T3-T2 : A = 2 T2-T1-T3 : A = 1 T2-T3-T1 : A = 2 Copyright (c) 20 03 C. J. Date page V .2 *** End of Introduction to Part V *** Copyright (c) 20 03 C. J. Date page 16.10 Copyright ... U1, U2, U3, again not necessarily in that order.) Ri-Rj-Rk-Up-Uq-Ur : 3 * 2 * 1 * 3 * 2 * 1 = 36 possibilities Ri-Rj-Up-Rk-Uq-Ur : 3 * 2 * 2 * 1 * 2 * 1...

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... are clearly more colored circles than there are circles. And colored circles can't be obtained from circles via S by C, either. Note the remark to the effect that "COLORED_CIRCLE ... operators specifically. OPERATOR ROTATE ( T RECTANGLE ) UPDATES T VERSION ROTATE_RECTANGLE ; Copyright (c) 20 03 C. J. Date page 21 .5 Recovery control: Explain two-phase commit ver...

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... Copyright (c) 20 03 C. J. Date page 21 .7 21 .3 See Section 21 .2. 21 .4 See Section 21 .4. 21 .5 See Section 21 .4. 21 .6 No answer provided. 21 .7 No answer provided. 21 .8 No answer ... the introductory remark: (Begin quote) The "views" mentioned in the titles of references [22 . 3 -2 2. 5], [22 .10], [22 . 12] , [22 .16], [22 .25 ], [22 .2...

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... 24 .6 .23 RES ( c1 , c2 ) *═ SPJ ( s, p, j, q ) AND S ( s, sn, st, c1 ) AND J ( j, jn, c2 ) ? *═ RES ( c1 , c2 ) 24 .6 . 24 RES ( p ) *═ SPJ ( s, p, j, q ) AND S ( s, sn, st, c ) AND J ( j, ... jn, c ) ? *═ RES ( p ) 24 .6 .25 Can't be done without negation. 24 .6 .26 RES ( p1, p2 ) *═ SPJ ( s, p1, j1 , q1 ) AND SPJ ( s, p2, j2 , q2 ) ? *═ RES ( p1...

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... that Copyright (c) 20 03 C. J. Date page 25 . 14 hierarchies at all, consisting of an "SP" class, a "PJ" class, and a "JS" class. 25 . 12 The performance factors ... and G by C are supported, type constraints are supported too, and noncircular circles and the like can't occur. (And run-time type errors specifically can occur only in the...

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... isn't well-formed if it involves (say) a left -to- right ordering to its attributes; if it involves a left -to- Copyright (c) 20 03 C. J. Date page 27 .20 explanation). In XML Schema, by contrast, ... </ProjectTuple> <ProjectTuple> <JNUM> ;J3 </JNUM> <JNAME>OCR</JNAME> <CITY>Athens</CITY> </ProjectTuple> <Projec...

Ngày tải lên: 06/08/2014, 01:21