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IDbDataAdapter.SelectCommand Property

Definition

Gets or sets an SQL statement used to select records in the data source.

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

Property Value

An IDbCommand that is used during Update(DataSet) to select records from data source for placement in the data set.

Examples

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

public static OleDbDataAdapter CreateCustomerAdapter(
    OleDbConnection connection)
{
    OleDbDataAdapter adapter = new OleDbDataAdapter();
    OleDbCommand command;

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

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

    adapter.SelectCommand = command;

    // Create the InsertCommand.
    command = new OleDbCommand(
        "INSERT INTO Customers (CustomerID, CompanyName) " +
        "VALUES (?, ?)", connection);

    command.Parameters.Add(
        "CustomerID", OleDbType.Char, 5, "CustomerID");
    command.Parameters.Add(
        "CompanyName", OleDbType.VarChar, 40, "CompanyName");

    adapter.InsertCommand = command;
    return adapter;
}
Public Shared Function CreateCustomerAdapter( _
    connection As OleDbConnection) As OleDbDataAdapter 

    Dim adapter As New OleDbDataAdapter()
    Dim command As OleDbCommand

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

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

    adapter.SelectCommand = command

    ' Create the InsertCommand.
    command = New OleDbCommand( _
        "INSERT INTO Customers (CustomerID, CompanyName) " & _
        "VALUES (?, ?)", connection)

    command.Parameters.Add( _
        "CustomerID", OleDbType.Char, 5, "CustomerID")
    command.Parameters.Add( _
        "CompanyName", OleDbType.VarChar, 40, "CompanyName")

    adapter.InsertCommand = command
    Return adapter
End Function

Remarks

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

If the SelectCommand does not return any rows, no tables are added to the DataSet, and no exception is raised.

Applies to