The long transaction and work management integration
Kevin W. Miller
FristEnergy Corp, 253 White Pond Drive
Akron, Ohio 44230
FristEnergy Corp, 253 White Pond Drive
Akron, Ohio 44230
The Long Transaction
PaperBackground
In this paper I will discuss the Long Transaction (LT) and its role in the Geographical Information System (GIS) -Work Management System (wMS) integration. I will explain at a high level what a Long Transaction is, why they are important in the GIS realm, and how they are applied. I will explain how the LT is affected by WMS / GIS integration. Finally, I will provide a high level view of the FirstEnergy Corp WMS / GIS integration with GIS long transactions.
Definition
A LT is an update to a database that takes longer than time required by hardware or software constraints. Business processes determine the time required for the transaction. The duration of a LT can range from a few minutes to a few years. The business need is based on the importance of storing information about a change in the system being modeled until the change actually occurs in the system. The goal is to capture future updates to a database during some process like planning or design.
Because the changes being captured have not occurred in the system being modeled, it is important that the changes do not affect the production view of the data presented to the user. It is beneficial if the user can identify areas where these changes are occurring and view them when needed. For example, if a planned or designed change to the modeled system includes the installation of a piece of equipment, system users might design changes using current production data for context. The change would be captured in a LT and could be displayed within the data as a change and not as the production data which would remain unchanged. When design changes were completed in the field and the equipment installed, the LT could be completed updating the production view of the database. This process could take years and the LT functionality must support this possibility.
To support business functions related to their normal life cycle, LTs are often designed to support a progression of stages. The LT must pass through these stages before being posted to production. The way the LTs data is presented or the functions that may preformed on the LT can be altered as the LT progresses through these stages. For instance, a LT may be created in an initiation stage. Then it may be moved to a design stage where changes required by the design are recorded and the data edited. The next stage could be a construction stage where the LT may be write protected. Finally, the LT could be moved to an as-built or closeout stage where post construction updates were recorded and the design is reconciled with the field construction. Business functions like material reconciliation can also be captured in this process. The stages are not required by the LT process but are driven by business requirements. This compliance with normal business functions adds value to LT functionality.
◆ 長事務開始後，其他用戶只能看到被鎖定區域在編輯之前的數據，而不能看到鎖定後的編輯情況，也不能對鎖定的數據進行編輯；
◆ 長事務可以持續幾天、幾個月甚至更長的時間，期間無需任何特殊處理，可以隨時繼續；
◆ 長事務中所作的修改具有相當的安全性，即使遇到突然斷電、死機或者其它意外情況，所編輯的數據也不會丟失或被破壞；
◆ 任何時候，如果對於所作的修改不滿意，可以回滾所作的修改，恢復到鎖定時的狀態；
◆ 編輯結束，只要提交了所作的修改，其他用戶立即就能看到修改後的內容；
◆ 只有提交或回滾了修改之後，其他用戶纔可以對原鎖定區域進行修改。
http://www.infoq.com/cn/articles/History-of-Extended-Transactions