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262 Solutions to Selected Exercises 6. H -> AXY 7. M -> NZ 8. MN -> HPT Step 1: N is extraneous due to M -> N in (7) 9. XY -> MNP Step 2: eliminate NP from the RHS due to M -> NP from (7,8) After Step 3, using the union axiom: 1. AC -> BDEGH Combining (1), (2), and (3) 2. AW->B 3. B -> ACF 4. H -> AXY 5. M -> HNPTZ Combining (7) and (8) 6. XY -> M Step 4, merging: 1. AC -> BDEFGH, B -> AC, H -> A using Rule 1 for AC being a super- key, Rule 2 for B being a superkey, the definition of 3NF, and A being a prime attribute. 3NF only. 2. AW->BG using Rule 1 for AW to be a superkey. BCNF. 3. H -> XY, XY -> M, and M -> HNPTZ using Rule 1 for H being a superkey (after taking H to its closure H -> XYMNPTZ), using Rule 2 for M being a superkey from M -> H, and Rule 2 for XY being a superkey from XY -> M. BCNF. Note: H->AXY is also possible here. Step 5, minimum set of normalized tables: Table 1: ABCDEFGH with superkeys AC, B (3NF only) Table 2: ABGW with superkey AW (3NF and BCNF) Table 3: HMNPTXYZ with superkeys H, XY, M (3NF and BCNF) Teorey.book Page 262 Saturday, July 16, 2005 12:57 PM 263 About the Authors Toby Teorey is a professor in the Electrical Engineering and Com- puter Science Department at the University of Michigan, Ann Arbor. He received his B.S. and M.S. degrees in electrical engineering from the University of Arizona, Tucson, and a Ph.D. in computer science from the University of Wisconsin, Madison. He was chair of the 1981 ACM SIGMOD Conference and program chair of the 1991 Entity-Relation- ship Conference. Professor Teorey’s current research focuses on data- base design and performance of computing systems. He is a member of the ACM. Sam Lightstone is a Senior Technical Staff Member and Develop- ment Manager with IBM’s DB2 Universal Database development team. He is the cofounder and leader of DB2’s autonomic computing R&D effort. He is also a member of IBM’s Autonomic Computing Architecture Board, and in 2003 he was elected to the Canadian Technical Excellence Council, the Canadian affiliate of the IBM Academy of Technology. His current research includes numerous topics in autonomic computing and relational DBMSs including automatic physical database design, adap- tive self-tuning resources, automatic administration, benchmarking methodologies, and system control. Mr. Lightstone is an IBM Master Inventor with over 25 patents and patents pending, and he has pub- lished widely on Autonomic Computing for relational database systems. He has been with IBM since 1991. Teorey.book Page 263 Saturday, July 16, 2005 12:57 PM 264 About the Authors Tom Nadeau is a senior technical staff member of Ubiquiti Inc. and works in the area of data and text mining. He received his B.S. degree in computer science and M.S. and Ph.D. degrees in electrical engineering and computer science from the University of Michigan, Ann Arbor. His technical interests include data warehousing, OLAP, data mining and machine learning. He won the best paper award at the 2001 IBM CASCON Conference. Teorey.book Page 264 Saturday, July 16, 2005 12:57 PM 265 Index Activity diagrams, 46–50 control flow icons, 46, 47 database design and, 50 decisions, 46, 47 defined, 34, 46 example, 49 flows, 46, 47 forks, 47–48 joins, 47, 48 nodes, 46, 47 notation description, 46–48 for workflow, 48–50 See also UML diagrams Aggregate functions, 222–24 Aggregation, 25 composition vs., 41 defined, 25 ER model, 101 illustrated, 25 UML constructs, 41 UML model, 102 AllFusion ERwin Data Modeler, 188–89 advantages, 211 DBMS selection, 199 ER modeling, 194 modeling support, 209 one-to-many relationships, 195 schema generation, 198 See also CASE tools Armstrong axioms, 122–24 Association rules, 179 Associations, 37–39 binary, 38–39 many-to-many, 39 many-to-many-to-many, 100 one-to-many, 39 one-to-many-to-many, 99 one-to-one, 39 one-to-one-to-many, 98 one-to-one-to-one, 97 reflexive, 37 ternary, 39 See also Relationships Attributes, 15–16 assignment, 19 attachment, 57 classifying, 57 Teorey.book Page 265 Saturday, July 16, 2005 12:57 PM 266 Index Attributes (cont’d.) data types, 214 defined, 15 descriptor, 15 extraneous, elimination, 125 identifier, 15, 16 multivalued, 15, 57 of relationships, 17, 19 ternary relationships, 28 UML notation, 35, 36 Automatic summary tables (AST), 166 Binary associations, 38–39 Binary recursive relationships, 90–92 ER model, 90 many-to-many, 90, 91, 92 one-to-many, 90, 91 one-to-one, 90–91 UML model, 91 See also Relationships Binary relationships, 85–89 many-to-many, 85, 87, 89, 104 one-to-many, 85, 87, 89 one-to-one, 85, 86, 88 See also Relationships Binomial multifractal distribution tree, 172 Boyce-Codd normal form (BCNF), 107, 115–16, 118 defined, 115 strength, 115 tables, 132, 133, 144 See also Normal forms Business intelligence, 147–86 data mining, 178–85 data warehousing, 148–66 defined, 147 OLAP, 166–78 summary, 185 Business system life cycle, 188 Candidate keys, 109, 110 Candidate tables from ER diagram transformation, 121–22 normalization of, 118–22 primary FDs, 119 secondary FDs, 119 See also Tables Cardenas’ formula, 170, 171 CASE tools, 1, 187–211 AllFusion ERwin Data Modeler, 188–89, 194, 195, 199, 211 application life cycle tooling integration, 202–4 basics, 192–96 collaborative support, 200–201 database generation, 196–99 database support, 199–200 data warehouse modeling, 207–9 defined, 187 design compliance checking, 204–5 development cycle, 190 DeZign for Databases, 190 distribution development, 201–2 ER/Studio, 190 introduction, 188–91 key capabilities, 191–92 low-end, 192 PowerDesigner, 188, 200, 203, 206, 210, 211 QDesigner, 190 Rational Data Architect, 188, 189, 193, 195, 198, 210 reporting, 206–7 script generation, 196 summary, 211 transformation table types, 192–93 value, 190–91 Visible Analyst, 190 XML and, 209–10 Chen notation, 9, 10 Class diagrams, 34–46 constructs illustration, 36 for database design, 37–43 Teorey.book Page 266 Saturday, July 16, 2005 12:57 PM . AC -> BDEGH Combining (1), (2), and (3) 2. AW->B 3. B -> ACF 4. H -> AXY 5. M -> HNPTZ Combining (7) and (8) 6. XY -> M Step 4, merging: 1. AC -> BDEFGH, B -> AC, H ->. Selected Exercises 6. H -> AXY 7. M -> NZ 8. MN -> HPT Step 1: N is extraneous due to M -> N in (7) 9. XY -> MNP Step 2: eliminate NP from the RHS due to M -> NP from (7,8) After. only. 2. AW->BG using Rule 1 for AW to be a superkey. BCNF. 3. H -> XY, XY -> M, and M -> HNPTZ using Rule 1 for H being a superkey (after taking H to its closure H -> XYMNPTZ),

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