The System.Data namespace provides access to classes that represent the ADO.NET architecture. ADO.NET lets you build components that efficiently manage data from multiple data sources.
In a disconnected scenario such as the Internet, ADO.NET provides the tools to request, update, and reconcile data in multiple tier systems. The ADO.NET architecture is also implemented in client applications, such as Windows Forms, or HTML pages created by ASP.NET.
The centerpiece of the ADO.NET architecture is the DataSet class. Each DataSet can contain multiple DataTable objects, with each DataTable containing data from a single data source, such as SQL Server.
Each DataTable contains a DataColumnCollection--a collection of DataColumn objects--that determines the schema of each DataTable. The DataColumn.DataType property determines the type of data held by the DataColumn. The DataColumn.ReadOnly and DataColumn.AllowDBNull properties let you further guarantee data integrity. The DataColumn.Expression property lets you construct calculated columns.
If a DataTable participates in a parent/child relationship with another DataTable, the relationship is constructed by adding a DataRelation to the DataRelationCollection of a DataSet object. When such a relation is added, a UniqueConstraint and a ForeignKeyConstraint are both created automatically, depending on the parameter settings for the constructor. The UniqueConstraint guarantees that values that are contained in a column are unique. The ForeignKeyConstraint determines what action will happen to the child row or column when a primary key value is changed or deleted.
Using the System.Data.SqlClient namespace (the.NET Framework Data Provider for SQL Server), the System.Data.Odbc namespace (the.NET Framework Data Provider for ODBC), the System.Data.OleDb namespace (the.NET Framework Data Provider for OLE DB), or the System.Data.OracleClient namespace (the .NET Framework Data Provider for Oracle), you can access a data source to use together with a DataSet. Each.NET Framework data provider has a corresponding DataAdapter that you use as a bridge between a data source and a DataSet.
Provides a description of the results of the query and its effect on the database.
Specifies how a command string is interpreted.
Specifies how conflicting changes to the data source will be detected and resolved.
Describes the current state of the connection to a data source.
Represents a constraint that can be enforced on one or more DataColumn objects.
Represents a collection of constraints for a DataTable.
Represents the exception that is thrown when attempting an action that violates a constraint.
Represents the schema of a column in a DataTable.
Provides data for the DataTable.ColumnChanging event.
Represents the method that will handle the DataTable.ColumnChanging event.
Represents the exception that is thrown when errors are generated using ADO.NET components.
Represents a parent/child relationship between two DataTable objects.
Represents a row of data in a DataTable.
Describes an action performed on a DataRow.
The DataRowBuilder type supports the .NET Framework infrastructure and is not intended to be used directly from your code.
Represents a collection of rows for a DataTable.
Gets the state of a DataRow object.
Describes the version of a DataRow.
Represents a customized view of a DataRow.
Represents an in-memory cache of data.
Marks a property, event, or extender with a description. Visual designers can display this description when referencing the member.
Represents one table of in-memory data.
Provides data for the DataTable.Clear method.
Represents the method that handles the DataTable.Clear method.
Represents the collection of tables for the DataSet.
Provides data for the DataTable.NewRow method.
Represents the method that handles the DataTable.NewRow method.
Represents a databindable, customized view of a DataTable for sorting, filtering, searching, editing, and navigation. The DataView does not store data, but instead represents a connected view of its corresponding DataTable. Changes to the DataView’s data will affect the DataTable. Changes to the DataTable’s data will affect all DataViews associated with it.
Describes the version of data in a DataRow.
Represents the default settings for DataView.ApplyDefaultSort, DataView.DataViewManager, DataView.RowFilter, DataView.RowStateFilter, DataView.Sort, and DataView.Table for DataViews created from the DataViewManager.
The exception that is thrown by the DataAdapter during an insert, update, or delete operation if the number of rows affected equals zero.
Specifies the data type of a field, a property, or a Parameter object of a .NET Framework data provider.
Represents the exception that is thrown when an action is tried on a DataRow that has been deleted.
Represents the exception that is thrown when a duplicate database object name is encountered during an add operation in a DataSet -related object.
Represents the method that will handle the DataAdapter.FillError event.
Represents an action restriction enforced on a set of columns in a primary key/foreign key relationship when a value or row is either deleted or updated.
Contains a collection of DataColumnMapping objects, and is implemented by the DataColumnMappingCollection, which is used in common by .NET Framework data providers.
Allows an object to implement a DataAdapter, and represents a set of methods and mapping action-related properties that are used to fill and update a DataSet and update a data source.
Represents a parameter to a Command object, and optionally, its mapping to DataSet columns; and is implemented by .NET Framework data providers that access data sources.
Collects all parameters relevant to a Command object and their mappings to DataSet columns, and is implemented by .NET Framework data providers that access data sources.
Provides a means of reading one or more forward-only streams of result sets obtained by executing a command at a data source, and is implemented by .NET Framework data providers that access relational databases.
Provides access to the column values within each row for a DataReader, and is implemented by .NET Framework data providers that access relational databases.
Represents an SQL statement that is executed while connected to a data source, and is implemented by .NET Framework data providers that access relational databases.
Represents an open connection to a data source, and is implemented by .NET Framework data providers that access relational databases.
Represents a set of command-related properties that are used to fill the DataSet and update a data source, and is implemented by .NET Framework data providers that access relational databases.
Used by the Visual Basic .NET Data Designers to represent a parameter to a Command object, and optionally, its mapping to DataSet columns.
Represents a transaction to be performed at a data source, and is implemented by .NET Framework data providers that access relational databases.
Provides the base functionality for creating collections.
Represents the exception that is thrown when incorrectly trying to create or access a relation.
Specifies the transaction locking behavior for the connection.
Contains a collection of TableMapping objects, and is implemented by the DataTableMappingCollection, which is used in common by .NET Framework data providers.
Identifies a list of connection string parameters identified by the KeyRestrictions property that are either allowed or not allowed.
Specifies how a DataColumn is mapped.
Occurs when a target and source DataRow have the same primary key value, and the DataSet.EnforceConstraints property is set to true.
Represents the method that will handle the DataSet.MergeFailed event.
Determines the action that occurs when a mapping is missing from a source table or a source column.
Represents the exception that is thrown when you try to access a row in a table that has no primary key.
Represents the exception that is thrown when you try to insert a null value into a column where DataColumn.AllowDBNull is set to false.
This exception is thrown when an ongoing operation is aborted by the user.
Specifies the type of a parameter within a query relative to the DataSet.
Specifies the attributes of a property.
Represents the exception that is thrown when you try to change the value of a read-only column.
Indicates the action that occurs when a ForeignKeyConstraint is enforced.
Indicates the schema serialization mode for a typed DataSet.
Specifies how to handle existing schema mappings when performing a DataAdapter.FillSchema(DataSet,SchemaType) operation.
Determines the serialization format for a DataSet.
Specifies SQL Server-specific data type of a field, property, for use in a SqlParameter.
Provides data for the state change event of a .NET Framework data provider.
Represents the method that will handle the DbConnection.StateChange event.
Provides additional information for the SqlCommand.StatementCompleted event.
The delegate type for the event handlers of the SqlCommand.StatementCompleted event.
The exception that is thrown by a strongly typed DataSet when the user accesses a DBNull value.
Used to create a strongly typed DataSet.
The exception that is thrown when a name conflict occurs while generating a strongly typed DataSet.
Represents a restriction on a set of columns in which all values must be unique.
Specifies how query command results are applied to the row being updated.
Specifies the action to take with regard to the current and remaining rows during an DbDataAdapter.Update(DataSet).
Represents the exception that is thrown when you try to return a version of a DataRow that has been deleted.
Specifies how to read XML data and a relational schema into a DataSet.
Specifies how to write XML data and a relational schema from a DataSet.