An Introduction to Database Systems 8Ed - C J Date - Solutions Manual Episode 1 Part 5 pptx

... decomposed (e.g., into decimal digits, or into integer and fractional parts) in suitable circumstances; so is a number atomic? What about bit and character strings, which are obviously decomposable? ... │ │ │ C │ │ │ a1 │ b1 │ c2 │ │ │ ├════┤ │ ├════┤ │ │ a1 │ b2 │ c1 │ │ │ │ b1 │ │ │ c1 │ │ │ a1 │ b2 │ c2 │ │ │ │ b2 │ │ │ c2 │ │ │ a2 │ b1 │ c1 │ │ │ └────┘ │ └────┘ │ │ a2 │ b1...

Ngày tải lên: 06/08/2014, 01:21

... RESTRICT specification) f. Accepted (project J4 and all shipments for project J4 are deleted) g. Accepted h. Rejected (candidate key uniqueness violation) Copyright (c) 2003 C. J. Date page ... SPJ, DELETE on S, DELETE on SPJ, UPDATE on S.S#, UPDATE on S.CITY, UPDATE on SPJ.S#, UPDATE on SPJ.QTY p. UPDATE on SPJ.QTY q. UPDATE on S.CITY 9 .5 a. Accepted b. Re...

Ngày tải lên: 06/08/2014, 01:21

... JOIN SPJ JOIN ( J RENAME CITY AS JCITY ) ) { SCITY, JCITY } 7.24 ( J JOIN SPJ JOIN S ) { P# } 7. 25 ( ( ( J RENAME CITY AS JCITY ) JOIN SPJ JOIN ( S RENAME CITY AS SCITY ) ) WHERE JCITY ... constraints, which is why Chapters 7 and 8 precede Chapter 9. Copyright (c) 2003 C. J. Date page 7 . 15 AND JCITY =/ SCITY ) { S#, P#, J# } 7. 21 P SEMIJOIN ( SPJ SEMIJOIN (...

Ngày tải lên: 06/08/2014, 01:21

... S#:SX, CITY:CITYX ) AND J ( J# :JY, CITY:CITYY ) AND SPJ ( S#:SX, J# :JY ) ) 8 . 15 .24 PX WHERE EXISTS SX EXISTS JX EXISTS CITYX ( S ( S#:SX, CITY:CITYX ) AND J ( J# :JX, CITY:CITYX ) AND SPJ ( ... SPJX .J# = JX .J# ) 8 .13 .24 SPJX.P# WHERE EXISTS SX EXISTS JX ( SX.CITY = JX.CITY AND SPJX.S# = SX.S# AND SPJX .J# = JX .J# ) 8 .13 . 25 SPJX .J# WHERE EXISTS SX EXISTS...

Ngày tải lên: 06/08/2014, 01:21

... 10 .18 .4 CREATE VIEW JC AS SELECT J. J#, J. CITY FROM J WHERE J. J# IN ( SELECT SPJ .J# FROM SPJ WHERE SPJ.S# = S# ( 'S1' ) ) AND J. J# IN ( SELECT SPJ .J# FROM SPJ WHERE SPJ.P# ... have to face up to questions such as: Does (e.g.) many -to- one mean a relationship that's inherently, necessarily many -to- one, or does it mean one that just happens to...

Ngày tải lên: 06/08/2014, 01:21

... such as those discussed earlier in the chapter don't occur with this relvar. Exercise: Check this claim." Answer: It's easy to see that Copyright (c) 2003 C. J. Date page 11 .5 ... answer provided. Candidate keys: L, DPC, and DPT. 11 .14 Abbreviating NAME, STREET, CITY, STATE, and ZIP * to N, R, C, T, and Z, respectively, we have: N → RCT RCT → Z Z → CT...

Ngày tải lên: 06/08/2014, 01:21