An Introduction to Database Systems 8Ed - C J Date - Solutions Manual Episode 1 Part 10 pot

... 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 An obviously ... Introduction to Part III *** Copyright (c) 2003 C. J. Date page 11 .4 is constrained to contain at most one tuple (for further discussion, see the answer to Exerci...

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 ( S...

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

... 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

... 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 JX...

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 ... EXISTS ( SELECT * FROM J AS JX WHERE EXISTS ( SELECT * FROM J AS JY WHERE ( JX .J# <> JY .J# AND JX.CITY = JY.CITY ) ) ) ) ; e. CREATE ASSERTION SQL_E CHECK ( ( SELECT...

Ngày tải lên: 06/08/2014, 01:21