ADO and ADO. Net (reproduced from msdn) Abstract: ADO and ADO. NET are a high-performance access information source policy provided by Microsoft. These technologies allow enterprises to easily integrate multiple data sources and create easy-to-maintain solutions. Directory 1. Introduction to ADO and ADO. Net 2. History of data access methods 3. Comparison between ADO and ADO. Net 4. Summary 1. Introduction to ADO and ADO. net. Both ADO and ADO. NET are similar and different. They can all write applications that can access and operate data on database servers. Program Easy to use, high speed, low memory consumption, and less disk space. It supports the main functions used to create Client/Server-based and Web applications. However, ADO uses ole db interfaces and is based on Microsoft's COM technology, while ADO. Net has its own ADO. net interface and is based on Microsoft's. NET architecture. As we all know, the. NET system is different from the com system, and the ADO. net interface is completely different from the ADO and ole db interfaces. That is to say, ADO. NET and ADO are two data access methods. 2. The history of data access methods below briefly review several stages of Microsoft's data access methods. ODBC-(Open Database Connectivity) is the first data access technology to access different relational databases using SQL. ODBC applications can be used to manipulate different databases through a single command. What developers need to do is to add the corresponding ODBC driver to different applications. Unlike ODBC, Dao-(data access objects) is intended for C/C ++ programmers. It is a simple data access method provided by Microsoft to Visual Basic developers, used to manipulate the ACCESS database. Rdo-when using Dao to access different relational databases, the jet engine had to convert commands between Dao and ODBC, leading to performance degradation, while rdo (Remote Data Objects) the appearance. Ole db-as more and more data is stored in non-relational format, a new architecture is required to provide seamless connection between such applications and data sources, based on COM (Component Object Model) ole db came into being. Ado-the ADO Based on ole db is simpler, more advanced, and more suitable for Visual Basic programmers. It eliminates the various drawbacks of ole db and is replaced by the Development Trend of Microsoft technology.
Ado architecture chart
3. Compared with ADO. net, when Microsoft began designing the. NET architecture, Microsoft decided to re-design the data access model so that it could be fully based on the XML and offline computing models. The main differences between the two are: ADO is stored in recordset, while ADO. NET is represented in dataset. The recordset looks more like a single table. If you want the recordset to be represented in multiple tables, you must connect multiple tables in SQL. Instead, dataset can be a set of multiple tables. The operation of ADO is an online method, which means that both browsing and updating data must be real-time. ADO. net is used offline, ADO. net will use XML to make a copy of the data, ADO.. Net databases must be connected online only during this period. Since ADO uses the COM technology, this requires that the data type used must comply with the COM specification, while ADO. net is based on the XML format, and the data types are more abundant and do not need to be converted due to the com orchestration, thus improving the overall performance. The following figure depicts the ADO. Net System.
ADO. NET architecture chart
4. Summary ADO. NET provides an Optimized Data Access Model for the. NET architecture, which is exactly the same as the com-based ADO. Author: Meng Qingchen
