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This article mainly shows you "what are the differences between ADO and RDO in the database", the content is simple and clear, and I hope it can help you solve your doubts. Let me lead you to study and learn "what are the differences between ADO and RDO in the database".

ADO: what encapsulation is it based on and what .dlls are used to connect? What components are needed to connect? OLE DB: how do you connect to multiple databases and what components are needed to connect? Relationship with ODBC? what does ADO have to do with them? it's just an object.

OLE DB,ODBC provides dynamic connection libraries for connecting databases. To deal with the database directly, you can refer to the ado and ado.net book ADO, that is, ActiveX DADO and RDOata Objects, which is provided by Microsoft to enable ASP to access the database Components. ADO bears some resemblance to RDO (Remote Data Objects). But it is said that ADO access is faster and requires less memory.

What is the standard of ODBC? MS company and database company set ~ ADO: what encapsulation is it based on, and what .dll is used to connect? What components are required to connect? Middleware, can VC/VB/DELPHI... Referenced (object concept) BDE: similar to the concept of ADO, it is a kind of middleware. (however, it is for Borland's own use)

Introduction to ADO.NET technology

Key points for creating ADO.NET applications

Introduction to the main points of using ADO.NET applications

How to better design ADO.NET and its skills

Talking in detail about the skills of using ADO.NET program and related matters

Let me also review: ODBC: open database connection standard. Provides a way to deal with data in a relational database independent of DBMS. (is a programming interface that enables applications to access DBMS through sql) OLE DB: an object-oriented interface that encapsulates database server functions and serves multiple database types. ADO and RDO

ADO.NET gives you obvious control over what data is returned from the data source and how much data is stored in the dataset. You can consider the following techniques when designing your application:

Avoid using DataAdapter.Fill, which uses startRecord and maxRecods values. When populating the dataset in this way, the data ADO and RDO sets populate only the number of records specified by the maxRecords parameter (starting with the records specified by the parameter startRecord), regardless of the entire query returned. This results in reading outdated "unwanted" records while using unnecessary server resources to return supplementary records.

One of the techniques used to return only one page of records at some point is to create a SQLADO and RDO statement that contains a WHERE and ORDER BY clause with a TOP decision. This technique relies on the method of identifying each row. When navigating to a record on the next page, modify the WHERE clause so that it contains all records with a * * identity larger than the current page identity; when navigating to the previous page, modify the WHERE clause so that it contains all records with a * * identity smaller than the current page identity. For both queries, only the record of the TOP page of the record is returned. The records need to be sorted in descending order when navigating to the previous page, which returns the last page of the query (you can reorder the records before display if necessary).

ADO and RDO

Another technique is to create a SQL statement that contains TOP decisions and embedded SELECT statements. This technique is not based on the method of identifying each row. The step of using this technique is to multiply the size of the page by the number of pages you want. The value is then passed to the TOP decision of the SQL query and sorted in ascending order. Then embed this query into another query, which selects the TOP page size from the embedded query results and sorts them in descending order. Essentially returns the end page of the embedded query. For example, to return the third page of a query with a page size of 10, use the following command.

DataAdapter uses the data in DataSet to update the new database of ADO and RDO through its Update method. When the data contained in the DataSet instance changes, the Update method is called, and DataAdapter analyzes the changes and executes the appropriate command (INSERT, UPDATE, or DELETE) to update the data in the database. If the DataTable in DataSet is mapped to or generated from a single database table

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