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Editor to share with you what skills to use ADO.NET DataSet, I believe that most people do not know much about it, so share this article for your reference, I hope you can learn a lot after reading this article, let's go to know it!

Benefits of using strong typing in 1.ADO.NET DataSet

Another benefit of DataSet is that it can be inherited to create a strongly typed DataSet. The benefits of strongly typed DataSet include design-time type checking and the benefits of Microsoft Visual Studio .NET for the termination of strongly typed DataSet statements. After you modify the schema or relational structure of the DataSet, you can create a strongly typed DataSet that exposes rows and columns as properties of the object rather than as items in the collection. For example, instead of exposing the name column of the rows in the customer table, expose the Name property of the Customer object. Typed DataSet derives from the DataSet class, so no functionality of DataSet is sacrificed. That is, typed DataSet can still be accessed remotely and provided as a data source for data-bound controls such as DataGrid. If the architecture is unknown in advance, you can still benefit from the capabilities of generic DataSet, but not from the additional capabilities of strongly typed DataSet.

Dealing with strongly typed null references in 2.ADO.NET DataSet use

When using strongly typed DataSet, you can annotate DataSet's XML Schema definition language (XSD) schema to ensure that strongly typed DataSet handles null references correctly. The nullValue annotation enables you to replace DBNull with a specified value String.Empty, keep a null reference, or throw an exception. Which option you choose depends on the context of the application. By default, an exception is thrown if a null reference is encountered.

For more information, see Working with a Typed DataSet.

3.ADO.NET DataSet uses refresh data

If you want to refresh the values in DataSet with the updated values on the server, use DataAdapter.Fill. If there is a primary key defined on DataTable, DataAdapter.Fill matches the new row based on the primary key and applies the value on the server when it is changed to an existing row. Even if you modify them before refreshing, the RowState of the refresh row is still set to Unchanged. Note that if no primary key is defined for DataTable, DataAdapter.Fill adds a new row with possible duplicate primary key values.

If you want to refresh the table with the current value from the server while retaining any changes made to the rows in the table, you must first populate the table with DataAdapter.Fill and populate a new DataTable, and then DataTableMerge into the DataSet with the preserveChanges value true.

4. Search for data in DataSet

When querying rows that match specific criteria in DataSet, index-based lookups can be used to improve search performance. When a PrimaryKey value is assigned to DataTable, an index is created. When you create a DataView for DataTable, an index is also created. Here are some tips for using index-based lookups.

If ◆ queries the columns of the PrimaryKey that make up DataTable, use DataTable.Rows.Find instead of DataTable.Select.

◆ for queries involving non-primary key columns, you can use DataView for multiple queries of data to improve performance. When the sort order is applied to the DataView, an index is created for the search. DataView exposes Find and FindRows methods to query data in the underlying DataTable.

If ◆ does not need a sorted view of the table, it can still take advantage of index-based lookups by creating a DataView for DataTable. Note that this is beneficial only if you perform multiple query operations on the data. If only a single query is executed, the processing required to create the index reduces the performance improvement caused by using the index.

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