Tài liệu, luận văn, đồ án, tiểu luận, đề tài về Công Nghệ Thông Tin
Outer join problems Type I nested queries Type II nested queries and difference problems Nested queries in the FROM clause Division problems Null value effects
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Overview of Physical Database Design File Structures Query Optimization Index Selection Additional Choices in Physical Database Design
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Modification anomalies Functional dependencies Major normal forms Relationship independence Practical concerns Modification Anomalies Unexpected side effect Insert, modify, and delete more data than desired Caused by excessive redundancies Strive for one fact in one place
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Guidelines for analyzing business information needs Transformations for generating alternative designs Finalizing an ERD Schema Conversion Characteristics of Business Data Modeling Problems Poorly defined Conflicting statements Wide scope Missing details Many stakeholders Requirements in many formats Add structure Eliminate irrelevant...
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Notation basics Understanding relationships Generalization hierarchies Business rule representation Diagram rules Alternative notations
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1. Background 2. Getting started 3. Joining tables 4. Summarizing tables 5. Problem solving guidelines 6. Advanced problems 7. Data manipulation statements What is SQL? Structured Query Language Language for database definition, manipulation, and control International standard Standalone and embedded usage Intergalactic database speak
45 trang | Chia sẻ: candy98 | Ngày: 28/11/2020 | Lượt xem: 588 | Lượt tải: 0
Relational model basics Integrity rules Rules about referenced rows Relational Algebra Tables Relational database is a collection of tables Heading: table name and column names Body: rows, occurrences of data
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Development Alternatives Difficulties Operational system is produced late Rush to begin implementation Requirements are difficult to capture Alternative methodologies Spiral approaches Rapid application development Prototypes may reduce risk
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First course in database management Practical textbook Fundamentals of relational databases Data modeling and normalization Database application development Database administration and database processing environments Detailed material
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1. Stack (Ngăn xếp) Giới thiệu Các thao tác cơ bản Các ứng dụng 2. Queue (Hàng Đợi) Giới thiệu Các thao tác cơ bản Ứng dụng
30 trang | Chia sẻ: candy98 | Ngày: 28/11/2020 | Lượt xem: 885 | Lượt tải: 1