Introduction to ADO. NET and ADO !!

Recently, I have seen some netizens asking about ADO. NET and ADO. NET does have this question. I want to help you with my understanding and experience! In fact, most of the things are still from MSDN !! For applications written using local code, ADO provides COM-based application-level interfaces for ole db data providers. Similar to ADO. NET, ADO supports various development needs, including creating front-end database clients and Middle-layer business objects using a live connection with relational databases and data in other storage areas. In addition, like ADO. NET, ADO can build client Record Sets, use loosely coupled record sets, and process data shaping row sets of ole db.
ADO also supports some behaviors that are not exposed through ADO. NET, such as server-side cursors that can be rolled. However, because server-side cursors need to save database resources, using them may have a significant negative impact on Application Performance and scalability. To transmit the ADO record set through the firewall, You need to configure the firewall to enable COM sending requests and consider the relevant security consequences. In addition, the data type is limited to the data types defined by the COM standard. You can choose to retain the ADO record set in XML format and transmit XML text.
ADO. NET is an important application-level interface used to provide data access services on the Microsoft. NET platform. In ADO. NET, you can use the new. NET Framework data provider to access the data source. The data providers include:
SQL Server. NET Framework data provider.
Ole db. NET Framework data provider.
ODBC. NET Framework data provider.
Oracle. NET Framework data provider.
These data providers can meet various development requirements, including intermediate layer Business Objects (they use active connections to data in relational databases and other storage areas ).
ADO. NET is designed for message-based Web applications and provides better functions for other application structures. By supporting loose and coupling access to data, ADO. NET reduces the number of active connections to the database (that is, it reduces the possibility of multiple users competing for limited resources on the database server), thus maximizing data sharing.
ADO. NET provides several data access methods. In some cases, Web applications or XML Web services need to access data from multiple sources or interoperate with other applications (including local and remote applications, you can also benefit from maintaining and transferring cache results. Using datasets is a wise choice. As a replacement method, ADO. NET provides data commands and data readers for direct communication with data sources. Database operations that are directly performed using data commands and data readers include running queries and stored procedures, creating database objects, and directly updating and deleting using DDL commands.