Introduction of Data integration

concept
Seeing the name and guessing the meaning is to logically or physically gather data from different sources, formats, and characteristics. Responsible for completing the extraction, conversion and loading of relevant data.
It can be simply understood as: data sharing is conducive to the integration of information
Note: The premise of data integration is that the integrated application must disclose the data structure

What problem to solve
Data integration achieves integration through data exchange between applications, mainly to solve the problem of data distribution and heterogeneity

classification
Federal database system:

It consists of an autonomous database system, which provides access interfaces to share data. It can be understood that we are a group or an alliance organization, we are in the same organization and the same group, we share all information. Open access interface is equivalent to providing a way and a condition, this way and condition are all to allow us to share data

This mode is divided into two cases, tight coupling and loose coupling. Tight coupling provides a unified access mode, which is generally static. Loose coupling does not need to provide a unified interface, data sources can be accessed through a unified language

Middleware mode:
Access heterogeneous databases through the global data model. Middleware is located between the data layer and the application layer. It coordinates data at the bottom and provides interfaces at the top to provide an advanced search service for heterogeneous data sources. It can be seen as an intermediary, it will coordinate and transform.

Data warehouse model
A data warehouse is a subject-oriented, integrated, time-related and unmodifiable collection of data in an enterprise for management and decision-making. In fact, it is a data integration in itself, but it is a data integration method proposed for a certain application area of the enterprise.


-Intergration Services:
From using the Intergration Services service provided in SQL Server Management Studion to monitor the operation of the Intergration Services package and manage the storage of the package

Intergration Services object model:
Including tools for accessing Intergration Services, command line tools, and native and managed APIs for custom applications

-When Intergration Services is running:
Save package layout and run package at runtime
Including event handlers and custom tasks

-Intergration Services data flow:
Encapsulate the data flow engine.
What does the data flow engine do?
It provides a buffer that moves data from the source to the memory gifted by the target, and calls the source that extracts data from files and relational databases. Manage the conversion of modified data and load the data so that the data can be used by other processes.
It can be summarized into two points, one is the movement and extraction of the source and the other is the data