1. Trang chủ
  2. » Công Nghệ Thông Tin

Database Modeling & Design Fourth Edition- P58 potx

4 195 0
Tài liệu đã được kiểm tra trùng lặp

Đang tải... (xem toàn văn)

THÔNG TIN TÀI LIỆU

Thông tin cơ bản

Định dạng
Số trang 4
Dung lượng 110,83 KB

Các công cụ chuyển đổi và chỉnh sửa cho tài liệu này

Nội dung

Trang 1

Primary FDs (cont’d.)

from ER diagram, 120

See also Functional dependencies

(FDs)

Primary keys, 109

constraints, 217

UML constructs, 42

QDesigner, 190

Query optimization, 177–78

Rational Data Architect, 188, 189, 211

automatic computing linkages, 198

ER modeling, 193

property editing, 195

XML adoption, 210

See also CASE tools

Rational MultiSite software, 201, 202

Redundant relationships, 58–60

analyzing, 58

illustrated, 59

See also Relationships

Referential integrity, 30, 227–28

Reflexive associations, 37

Relational databases (RDBs), 150, 151

Relationships, 14–15

attributes, 17, 19

binary, 85–89

binary recursive, 90–92

cardinality, 18

connectivity, 17, 18–19

defined, 14

defining, 58–61

degree, 16–17

entity existence in, 19–20

many-to-many, 14, 18, 39

many-to-many-to-many, 96, 137

multiple, 103

names, 15

n-ary, 28–29, 92–100

one-to-many, 14, 18, 39

one-to-many-to-many, 95

one-to-one, 14, 18, 39

one-to-one-to-many, 94 one-to-one-to-one, 93 packages, 44

redundant, 58–60 roles, 15

ternary, 16, 25–28, 60–61, 92–100 Reporting, 206–7

elements, 206–7 PowerDesigner, 206

See also CASE tools

Requirements analysis, 3, 54–55 defined, 54

objectives, 55 results, 140 Requirements specification, 139–40 Reverse engineering, 6

Roles, 15 Rows, 2 Schemas commonality, 72 comparison, 68 conceptual integration, 67 conformation, 68–69 diversity, 66

merging, 69 restructuring, 69 structural conflicts, 68, 71 Secondary FDs, 118, 119 candidate table, 119 determining, 120 from requirements specification,

121

See also Functional dependencies

(FDs) Second normal form (2NF), 111–13 functional dependence, 111 tables, 112, 113

See also Normal forms

Select command, 219 Semi-structured data, 209–10 Set operators, 214

Snowflake schema, 156, 157

Trang 2

Software Development Platform, 204

Specialization, 24

SQL, 213–29

advanced value expressions,

214–15 aggregate functions, 222–24 basics, 213–29

comparison operators, 214 conceptual data model

transformation to, 6, 83–106

constructs, 83–85 data types, 214 DDL, 215–18 defined, 213 DML, 218–29 joins, 224–26 logical operators, 214 names, 214

null values, 84–85 object definitions, 215 referential integrity, 227–28 set functions, 214

set operators, 214 subqueries, 224–26 update commands, 226–77 SQL tables, 83, 84

with embedded foreign key, 84 from relationships, 84

with same information content, 84 Star schema, 154–56

defined, 154 dimensions, 162 for estimating process, 160 example, 154

for job costing daily snapshot, 166 for job costing process, 165

for productivity tracking process,

163 queries, 154–55 for scheduling process, 162

See also Data warehouses

Stereotypes, 43

Subqueries, 224–26 Subtypes, 23–24 defined, 23 entities, 24 illustrated, 23 Superkeys defined, 109 rules, 123–24 Supertypes, 23–24 defined, 23 illustrated, 23 Tables

Boyce-Codd normal form (BCNF),

132, 133, 144 candidate, 118–22 decomposition of, 145 fourth (4NF) normal form, 131,

132–33 merge of, 126 normalized, 6, 116–18 reduction of, 145 second normal form (2NF), 112,

113 third (3NF) normal form, 114,

122–27 Ternary associations, 39 Ternary relationships, 16, 25–28,

92–100 attributes, 28 connectivity, 61 defining, 60 entities in, 25–26

ER model, 93–96 foreign key constraints and, 92 forms, 28

illustrated, 26–27, 60 many-to-many-to-many, 96, 100 with multiple interpretations, 130 one-to-many-to-many, 95, 99 one-to-one-to-many, 94, 98 one-to-one-to-one, 93, 97 requirement, 25

Trang 3

Ternary relationships (cont’d.)

transformation, 105

UML, 97–100

varieties, 92

See also Relationships

Text mining, 181–85

verbatim description, 184

verbatim description information,

184

word mapping, 184–85

See also Data mining

Third (3NF) normal form, 113–15,

118

defined, 114

synthesis algorithm, 124–25

tables, 114

tables, minimum set, 122–27

See also Normal forms

Transformation, 6, 83–106

entity, 104

ER-to-SQL example, 105

many-to-many binary relationship,

104

rules, 83–85

steps, 103–5

summary, 106

ternary relationship, 105

Triple exponential smoothing, 180,

182

UML diagrams

activity, 34, 46–50

class, 33–46

conceptual data model, 142

ER models vs., 33

generalization and aggregation, 102

many-to-many binary relationship,

89

one-to-many binary relationship,

89

one-to-one binary relationship, 88

organization, 51

size, 50

textual descriptions, 50–51 type, 33

Unified Modeling Language (UML), 9,

33–51 aggregation constructs, 41 defined, 33

generalization constructs, 40

n-ary relationship, 42

primary key constructs, 42 relationship types, 38 stereotypes, 43 summary, 51 usage rules, 50–51

See also UML diagrams

Union command, 221–22 Unique constraints, 216–17 Update anomaly, 112 Update commands, 226–27 View integration, 5–6, 66–74 defined, 66

example, 69–74 illustrated, 70, 71, 72–73 merged schema, 72–73 preintegration analysis, 67–68 process, 74

schema comparison, 68 schema conformation, 68–69 schema merge/restructure, 69 techniques, 69

type conflict, 71 Views, 166

coordinates of, 178 creating, 229 dynamic selection, 176

ER modeling based on

requirements, 61–63 exponential explosion, 167–69 size estimation, 170–72

SQL, 228–29 state estimation, 170–72 uses, 228

Visible Analyst, 190

Trang 4

Weak entities, 16, 103

XML, 207, 209–10

defined, 209 documents, 210 schema, 209 standards, 209

Ngày đăng: 05/07/2014, 05:20

TỪ KHÓA LIÊN QUAN