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This article mainly explains "how to understand the ADO.NET class library". Interested friends may wish to have a look. The method introduced in this paper is simple, fast and practical. Now let the editor take you to learn "how to understand the ADO.NET class library"!

An optional keyword in the ADO.NET class library that can be used in the name of the table or table variable that will receive data between the INSERT and the target table.

Specifies one or more table hints allowed by the target table. The WITH keyword and parentheses are required. READPAST, NOLOCK, and READUNCOMMITTED are not allowed in the ADO.NET class library.

The name and optional alias of the view. Views referenced by view_name must be updatable. Changes made by the INSERT statement cannot affect multiple base tables referenced in the view's FROM clause. For example, an INSERT in a multi-table view must use column_list,column_list to reference only columns from one base table.

Is an OPENQUERY or OPENROWSET function. For more information, see OPENQUERY and OPENROWSET. A list of one or more columns into which the ADO.NET class library inserts data. Column_list must be enclosed in parentheses and separated by commas.

If a column is not in column_list, Microsoft ®SQL Server ™must be able to provide a value based on the definition of the column; otherwise, the row cannot be loaded. In the ADO.NET class library, SQL Server automatically provides a value for the column if the column meets the following conditions: it has the IDENTITY attribute. Use the next incremental identification value. There is a default value. Use the default value of the column.

Has a timestamp data type. Use the current timestamp value. It's empty. Use null values. When inserting explicit values into identity columns, the ADO.NET class library must use column_list and VALUES lists, and for tables, the SET IDENTITY_INSERT option must be ON.

VALUES introduces a list of data values to insert. There must be a data value for each column in the column_list (if specified) or in the table. You must enclose the values list in parentheses.

The first two methods operate on the disconnected recordsets and read information from the client cache. In addition, the first two methods are often used in WEB-oriented environments and brand-new n-tier systems.

In ADO, all of these methods correspond to different types of cursors. In this article, you will find that although ADO.NET class library is different from ADO, it has all the functions of ADO. By contrast, your code will extract data from the actual data source and its physical storage media and formats.

The ADO.NET class library enables DataSet and DataReader to extract data from data sources. The former is a cache recorded in memory, which you can access from any direction and modify at will. The latter is a highly optimized object that moves forward only in a read-only recordset. Note: DataSet looks like a static cursor, but in fact, in .NET, ADO read-only cursors correspond to DataReader objects.

At this point, I believe you have a deeper understanding of "how to understand the ADO.NET class library". You might as well do it in practice. Here is the website, more related content can enter the relevant channels to inquire, follow us, continue to learn!

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