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Large efforts with much coordination across departments Enterprise data model Important artifact of data warehouse project Structure of data model Meta data for data transformation Top-down vs. bottom-up business architectures

56 trang | Chia sẻ: huyhoang44 | Ngày: 16/03/2020 | Lượt xem: 1012 | Lượt tải: 0

Concurrency control Recovery management Service characteristics Transparent Consume significant resources Significant cost component Transaction design important

49 trang | Chia sẻ: huyhoang44 | Ngày: 16/03/2020 | Lượt xem: 1045 | Lượt tải: 0

Data administrator Develops enterprise data model Establishes inter database standards Negotiates contractual terms Database administrator Performs database development tasks Consults on application development Evaluates DBMS capabilities and features

46 trang | Chia sẻ: huyhoang44 | Ngày: 16/03/2020 | Lượt xem: 1119 | Lượt tải: 0

Entity type rule 1-M relationship rule M-N relationship rule Identification dependency rule

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Create an ERD to represent a form ERD supports form and other anticipated processing ERD should be consistent with the form ERD is a view of the database

43 trang | Chia sẻ: huyhoang44 | Ngày: 16/03/2020 | Lượt xem: 974 | Lượt tải: 0

Data type mapping Processing orientation SELECT USING for single row results Cursor for multiple row results Cursor is similar to a dynamic array Interface provides statements or procedures to declare, open, close, iterate (position), and retrieve values

48 trang | Chia sẻ: huyhoang44 | Ngày: 16/03/2020 | Lượt xem: 1146 | Lượt tải: 0

Must rename columns: - derived columns - multiple columns with the same unqualified names (CourseNo from Offering and Course) Example 2: - Row summaries - Derived column: NumStudents - Must provide a name for all columns when one column is renamed - Positional notation for column names Access: - Use AS in the SELECT clause for de...

36 trang | Chia sẻ: huyhoang44 | Ngày: 16/03/2020 | Lượt xem: 1093 | Lượt tải: 0

Query execution: - For each Faculty row, execute nested query on the Student table - Faculty row does not qualify in the result unless it does not match any Student rows.

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Type I nested query with NOT IN condition One-sided outer join with IS NULL condition Difference operation using MINUS (EXCEPT) operator

37 trang | Chia sẻ: huyhoang44 | Ngày: 16/03/2020 | Lượt xem: 1221 | Lượt tải: 0

Minimize response time to access and change a database. Minimizing computing resources is a substitute measure for response time. Database resources Physical record transfers CPU operations Communication network usage (distributed processing)

70 trang | Chia sẻ: huyhoang44 | Ngày: 16/03/2020 | Lượt xem: 1140 | Lượt tải: 1