Package is a design concept of how to divide the functionality of the system. You don't know how a thing is implemented but you can go with it. This means that you may change what you think to be reality, and you can modify it later without affecting other components of the system. As people often say, the package is a black box, you can define how to do something, but don't tell you how you do it. For example, such as your bank. How does the bank save your account information? Large machine, small machine, or PC? What database is used? Which operating system? This will not cause your attention, because the bank has packaged them on the account services they provide. What you have to do is to tell the salesperson which transaction you want to do.
In this chapter, I will describe the concept of "database package layer", browse the "role of agile database design", different packaging technology, and "implementation strategy" related to database packaging. Let's assume that you are using the relational database.
Content list:
Data encapsulation layer agility database design Role package layer architecture Implementation policy column Error handling involved and recommended reading
1, data package layer.
The database encapsulation layer uses the business code to hide your database details, including its physical model. Service Objects Persistent Layer Service for Your Business - You can read data, write data, and delete data. The ideal business object is not known how the data is persisted. The data package layer does not have a magic nor theory's theory, and the data package layer is part of a large system or a small system, a single system or a composite system. The data package layer is a very important technique that the developer of each agile software should know and prepare for use.
An effective data package layer has the following benefits:
Reduce the coupling between your data entities and object entities to increase your ability to expand any one of them. Realize all your data relationship code in a place. Simplify the work of the programmer. Make programmers pay attention to business problems and agile database design. Give you a public place to achieve data-oriented business rules. Extend software performance with data detail.
Several disadvantages of a potential data seal layer:
It is necessary to invest in an appropriate clear mapping. Too many trivial data access controls.
2, the role of agility DBA
Figure 1: Role of agility DBA
3, package layer architecture
