Project/Area Number |
16K00152
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Multi-year Fund |
Section | 一般 |
Research Field |
Multimedia database
|
Research Institution | Ochanomizu University |
Principal Investigator |
|
Research Collaborator |
ISHII Tatsuo
NAGATA Yugo
|
Project Period (FY) |
2016-04-01 – 2019-03-31
|
Project Status |
Completed (Fiscal Year 2018)
|
Budget Amount *help |
¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000)
Fiscal Year 2018: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000)
Fiscal Year 2017: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000)
Fiscal Year 2016: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000)
|
Keywords | データベース / リレーショナルデータベース / ビューサポート / 更新可能性 / PostgreSQL / 意図に基づくアプローチ / 更新意図の外形的推測に基づくアプローチ / ビュー / ビューの更新可能性 / 制約充足問題 / SQL / 関係データベース / PopstgreSQL |
Outline of Final Research Achievements |
As views are virtual, the updatability of views poses a difficult problem known as the view update problem. To resolve the problem, many investigations were conducted, but updatable views within the conventional approach were extremely limited. In this research, it is shown that the limitation comes from because the updatability of views has been discussed at the database "schema level," and by arguing it at the "instance level," it is shown that Cartesian product views and join views become updatable under certain circumstances which are not updatable in the conventional approach. This novel approach is named as the pro forma guessing of update intention approach, also known as the intention-based approach. An algorithm to decide whether a generally defined view is updatable or not with respect to an update operation issued to it under the intention-based approach is shown. To examine the feasibility of the novel approach, it was prototyped as an extension of PostgreSQL 10.
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Academic Significance and Societal Importance of the Research Achievements |
本研究を遂行した結果,リレーショナルデータベースにおいて,これまで理論的にも実践的にも極めて限定的なビューの更新可能性を,「更新意図の外形的推測に基づくビューの更新可能性」というこれまでにない新しい考え方のもと,極限にまで高めることが可能であることを示した学術的意義は大きいと考えられる.データベースの現場で多用される直積ビューや結合ビューがこの新規アプローチの下で場合により更新可能となる恩恵は大きく,加えて,これをオープンソースのリレーショナルDBMSとして多くの情報処理の現場で稼働しているPostgreSQL上で実装し,その実現可能性を示し得たことも,社会的意義が大きいと考えられる.
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