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SqlCeDataAdapter.DeleteCommand Property

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

Namespace:  System.Data.SqlServerCe
Assembly:  System.Data.SqlServerCe (in System.Data.SqlServerCe.dll)

public SqlCeCommand DeleteCommand { get; set; }

Property Value

Type: System.Data.SqlServerCe.SqlCeCommand
A SqlCeCommand used during Update to delete records in the data source that correspond to deleted rows in the DataSet.

During a call to 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 and use the SqlCeCommandBuilder. Then, any additional commands that you do not set are generated by the SqlCeCommandBuilder. This generation logic requires key column information to be present in the DataSet.

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

The following example creates a SqlCeDataAdapter and sets some of its properties.

SqlCeCommand cmd = null;
SqlCeDataAdapter adp = null;

try
{
    adp = new SqlCeDataAdapter();
    SqlCeConnection conn = new SqlCeConnection("Data Source = MyDatabase.sdf");

    // Create the SelectCommand
    //
    cmd = conn.CreateCommand();
    cmd.CommandText = "SELECT * FROM Orders WHERE [Ship Country] = @country AND [Ship City] = @city";
    cmd.Parameters.Add("@country", SqlDbType.NVarChar, 15);
    cmd.Parameters.Add("@city", SqlDbType.NVarChar, 15);

    cmd.Parameters["@country"].Value = "UK";
    cmd.Parameters["@city"].Value = "London";

    adp.SelectCommand = cmd;

    // Create the DeleteCommand
    //
    cmd = conn.CreateCommand();
    cmd.CommandText = "DELETE FROM Orders WHERE [Order ID] = @orderID";

    SqlCeParameter p = cmd.Parameters.Add("@orderID", SqlDbType.NChar, 5, "Order ID");
    p.SourceVersion = DataRowVersion.Original;

    adp.DeleteCommand = cmd;

    // Populate the dataset with the results from the SELECT statement
    //
    DataSet ds = new DataSet();
    adp.Fill(ds);

    // Modify the dataset
    //
    MessageBox.Show("Number of rows: " + ds.Tables[0].Rows.Count);

    // Delete some rows
    //
    ds.Tables[0].Rows[3].Delete();
    ds.Tables[0].Rows[4].Delete();

    // This will execute two DELETE statements 
    //
    adp.Update(ds.Tables[0]);
}
catch (Exception e)
{
    MessageBox.Show(e.Message);
}
finally
{
    if (null != adp.SelectCommand) adp.SelectCommand.Dispose();
    if (null != adp.DeleteCommand) adp.DeleteCommand.Dispose();
}


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