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5. Two paradigms of pattern recognition There are several paradigms which have been used to solve the pattern recognition problem. The two main ones are statistical pattern recognition and syntactic pattern recognition In statistical pattern recognition, we use vector spaces to represent patterns and classes. The abstractions deal with probabili...
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Recap Designing a Set of Relations Properties of Relational Decompositions Algorithms for Relational Database Schema Multivalued Dependencies and Fourth Normal Form Join Dependencies and Fifth Normal Form Inclusion Dependencies Other Dependencies and Normal Forms
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Chapter Outline Informal Design Guidelines for Relational Databases Functional Dependencies (FDs) Definition, Inference Rules, Equivalence of Sets of FDs, Minimal Sets of FDs Normal Forms Based on Primary Keys General Normal Form Definitions (For Multiple Keys) BCNF (Boyce-Codd Normal Form)
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Summary Assertions provide a means to specify additional constraints Triggers are assertions that define actions to be automatically taken when certain conditions occur Views create temporary (virtual) tables A database may be accessed in an interactive mode Most often, however, data in a database is manipulate via application pro...
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Recap of SQL Queries
A query in SQL can consist of up to six clauses, but only
the first two, SELECT and FROM, are mandatory. The
clauses are specified in the following order:
SELECT 13 trang | Chia sẻ: vutrong32 | Ngày: 17/10/2018 | Lượt xem: 1805 | Lượt tải: 0 Chapter Summary
ER-to-Relational Mapping Algorithm
Step 1: Mapping of Regular Entity Types
Step 2: Mapping of Weak Entity Types
Step 3: Mapping of Binary 1:1 Relation Types
Step 4: Mapping of Binary 1:N Relationship Types.
Step 5: Mapping of Binary M:N Relationship Types.
Step 6: Mapping of Multivalued attributes.
Step 7: Ma... 6 trang | Chia sẻ: vutrong32 | Ngày: 17/10/2018 | Lượt xem: 1089 | Lượt tải: 1 QBE: A Query Language Based on
Domain Calculus (Appendix C)
The language is very user-friendly, because it
uses minimal syntax.
QBE was fully developed further with facilities for
grouping, aggregation, updating etc. and is
shown to be equivalent to SQL.
The language is available under QMF (Query
Management Facility) of DB2 of IBM and... 6 trang | Chia sẻ: vutrong32 | Ngày: 17/10/2018 | Lượt xem: 1176 | Lượt tải: 0 Summary
Presented Relational Model Concepts
Definitions
Characteristics of relations
Discussed Relational Model Constraints and Relational Database Schemas
Domain constraints’
Key constraints
Entity integrity
Referential integrity
Described the Relational Update Operations and Dealing with Constraint Violations 8 trang | Chia sẻ: vutrong32 | Ngày: 17/10/2018 | Lượt xem: 1140 | Lượt tải: 0 Summary
Introduced the EER model concepts
Class/subclass relationships
Specialization and generalization
Inheritance
These augment the basic ER model concepts introduced in Chapter 3
EER diagrams and alternative notations were presented 8 trang | Chia sẻ: vutrong32 | Ngày: 17/10/2018 | Lượt xem: 1014 | Lượt tải: 0 Chapter Summary
ER Model Concepts: Entities, attributes, relationships
Constraints in the ER model
Using ER in step-by-step conceptual schema
design for the COMPANY database
ER Diagrams - Notation
Alternative Notations – UML class diagrams, others 8 trang | Chia sẻ: vutrong32 | Ngày: 17/10/2018 | Lượt xem: 1445 | Lượt tải: 0
[WHERE