OdbcDataAdapter.SelectCommand Propiedad

Definición

Obtiene o establece la instrucción SQL o el procedimiento almacenado utilizado para seleccionar registros del origen de datos.Gets or sets an SQL statement or stored procedure used to select records in the data source.

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

Valor de propiedad

OdbcCommand

OdbcCommand que se utiliza durante una operación de relleno para seleccionar registros del origen de datos y colocarlos en DataSet.An OdbcCommand that is used during a fill operation to select records from data source for placement in the DataSet.

Ejemplos

En el ejemplo siguiente se crea un OdbcDataAdapter y se establecen las SelectCommand InsertCommand propiedades y.The following example creates an OdbcDataAdapter and sets the SelectCommand and InsertCommand properties. Se supone que ya ha creado un OdbcConnection objeto.It assumes that you have already created an OdbcConnection object.

public static OdbcDataAdapter CreateDataAdapter(
    OdbcConnection connection)
{
    string selectCommand =
        "SELECT CustomerID, CompanyName FROM Customers";

    OdbcDataAdapter adapter = new OdbcDataAdapter(
        selectCommand, connection);
    adapter.MissingSchemaAction = MissingSchemaAction.AddWithKey;

    // Create the Insert, Update and Delete commands.
    adapter.InsertCommand = new OdbcCommand(
        "INSERT INTO Customers (CustomerID, CompanyName) " +
        "VALUES (?, ?)");

    adapter.UpdateCommand = new OdbcCommand(
        "UPDATE Customers SET CustomerID = ?, CompanyName = ? " +
        "WHERE CustomerID = ?");

    adapter.DeleteCommand = new OdbcCommand(
        "DELETE FROM Customers WHERE CustomerID = ?");

    // Create the parameters.
    adapter.InsertCommand.Parameters.Add("@CustomerID",
        OdbcType.Char, 5, "CustomerID");
    adapter.InsertCommand.Parameters.Add("@CompanyName",
        OdbcType.VarChar, 40, "CompanyName");

    adapter.UpdateCommand.Parameters.Add("@CustomerID",
        OdbcType.Char, 5, "CustomerID");
    adapter.UpdateCommand.Parameters.Add("@CompanyName",
        OdbcType.VarChar, 40, "CompanyName");
    adapter.UpdateCommand.Parameters.Add("@oldCustomerID",
        OdbcType.Char, 5, "CustomerID").SourceVersion =
        DataRowVersion.Original;

    adapter.DeleteCommand.Parameters.Add("@CustomerID",
        OdbcType.Char, 5, "CustomerID").SourceVersion =
        DataRowVersion.Original;

    return adapter;
}
Public Function CreateDataAdapter( _
    ByVal connection As OdbcConnection) As OdbcDataAdapter

    Dim selectCommand As String = _
        "SELECT CustomerID, CompanyName FROM Customers"
    Dim adapter As OdbcDataAdapter = _
        New OdbcDataAdapter(selectCommand, connection)

    adapter.MissingSchemaAction = MissingSchemaAction.AddWithKey

    ' Create the Insert, Update and Delete commands.
    adapter.InsertCommand = New OdbcCommand( _
        "INSERT INTO Customers (CustomerID, CompanyName) " & _
         "VALUES (?, ?)")

    adapter.UpdateCommand = New OdbcCommand( _
        "UPDATE Customers SET CustomerID = ?, CompanyName = ? " & _
        "WHERE CustomerID = ?")

    adapter.DeleteCommand = New OdbcCommand( _
        "DELETE FROM Customers WHERE CustomerID = ?")

    ' Create the parameters.
    adapter.InsertCommand.Parameters.Add( _
        "@CustomerID", OdbcType.Char, 5, "CustomerID")
    adapter.InsertCommand.Parameters.Add( _
        "@CompanyName", OdbcType.VarChar, 40, "CompanyName")

    adapter.UpdateCommand.Parameters.Add( _
        "@CustomerID", OdbcType.Char, 5, "CustomerID")
    adapter.UpdateCommand.Parameters.Add( _
        "@CompanyName", OdbcType.VarChar, 40, "CompanyName")
    adapter.UpdateCommand.Parameters.Add( _
        "@oldCustomerID", OdbcType.Char, 5, "CustomerID").SourceVersion = _
        DataRowVersion.Original

    adapter.DeleteCommand.Parameters.Add( _
        "@CustomerID", OdbcType.Char, 5, "CustomerID").SourceVersion = _
        DataRowVersion.Original

    Return adapter
End Function

Comentarios

Cuando SelectCommand se asigna a un creado previamente OdbcCommand , OdbcCommand no se clona.When SelectCommand is assigned to a previously created OdbcCommand, the OdbcCommand is not cloned. En su lugar, SelectCommand mantiene una referencia al objeto creado previamente OdbcCommand .Instead, the SelectCommand maintains a reference to the previously created OdbcCommand object.

Si no SelectCommand devuelve ninguna fila, no se agrega ninguna tabla a DataSet , y no se genera ninguna excepción.If SelectCommand returns no rows, no tables are added to the DataSet, and no exception is raised.

Se aplica a