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IDbDataAdapter.DeleteCommand Property

Definition

Gets or sets an SQL statement for deleting records from the data set.

public:
 property System::Data::IDbCommand ^ DeleteCommand { System::Data::IDbCommand ^ get(); void set(System::Data::IDbCommand ^ value); };
public System.Data.IDbCommand? DeleteCommand { get; set; }
public System.Data.IDbCommand DeleteCommand { get; set; }
member this.DeleteCommand : System.Data.IDbCommand with get, set
Public Property DeleteCommand As IDbCommand

Property Value

An IDbCommand used during Update(DataSet) to delete records in the data source for deleted rows in the data set.

Examples

The following example creates an instance of the inherited OleDbDataAdapter class, and sets the SelectCommand and DeleteCommand properties. It assumes you have already created an OleDbConnection object.

public static OleDbDataAdapter CreateCustomerAdapter(
    OleDbConnection connection)
{
    OleDbDataAdapter dataAdapter = new OleDbDataAdapter();
    OleDbCommand command;
    OleDbParameter parameter;

    // Create the SelectCommand.
    command = new OleDbCommand("SELECT CustomerID FROM Customers " +
        "WHERE Country = ? AND City = ?", connection);

    command.Parameters.Add("Country", OleDbType.VarChar, 15);
    command.Parameters.Add("City", OleDbType.VarChar, 15);

    dataAdapter.SelectCommand = command;

    // Create the DeleteCommand.
    command = new OleDbCommand(
        "DELETE * FROM Customers WHERE CustomerID = ?",
        connection);

    parameter = command.Parameters.Add(
        "CustomerID", OleDbType.Char, 5, "CustomerID");
    parameter.SourceVersion = DataRowVersion.Original;

    dataAdapter.DeleteCommand = command;

    return dataAdapter;
}
Public Shared Function CreateCustomerAdapter( _
    connection As OleDbConnection) As OleDbDataAdapter 

    Dim dataAdapter As New OleDbDataAdapter()
    Dim command As OleDbCommand
    Dim parameter As OleDbParameter

    ' Create the SelectCommand.
    command = New OleDbCommand("SELECT CustomerID FROM Customers " & _
        "WHERE Country = ? AND City = ?", connection)

    command.Parameters.Add("Country", OleDbType.VarChar, 15)
    command.Parameters.Add("City", OleDbType.VarChar, 15)

    dataAdapter.SelectCommand = command

    ' Create the DeleteCommand.
    command = New OleDbCommand( _
        "DELETE * FROM Customers WHERE CustomerID = ?", _
        connection)

    parameter = command.Parameters.Add( _
        "CustomerID", OleDbType.Char, 5, "CustomerID")
    parameter.SourceVersion = DataRowVersion.Original

    dataAdapter.DeleteCommand = command

    Return dataAdapter
End Function

Remarks

During Update, if this property is not set and primary key information is present in the DataSet, the DeleteCommand can be generated automatically if you set the SelectCommand property of a .NET Framework data provider. Then, any additional commands that you do not set are generated by the CommandBuilder. This generation logic requires key column information to be present in the DataSet. For more information see Generating Commands with CommandBuilders.

When DeleteCommand is assigned to a previously created IDbCommand, the IDbCommand is not cloned. The DeleteCommand maintains a reference to the previously created IDbCommand object.

Applies to