OdbcDataAdapter.SelectCommand Propiedad
Definición
Importante
Parte de la información hace referencia a la versión preliminar del producto, que puede haberse modificado sustancialmente antes de lanzar la versión definitiva. Microsoft no otorga ninguna garantía, explícita o implícita, con respecto a la información proporcionada aquí.
Obtiene o establece la instrucción SQL o el procedimiento almacenado utilizado para seleccionar registros del origen de datos.
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 que se utiliza durante una operación de relleno para seleccionar registros del origen de datos y colocarlos en DataSet.
Ejemplos
En el ejemplo siguiente se crea y OdbcDataAdapter se establecen las SelectCommand propiedades y InsertCommand . Se supone que ya ha creado un OdbcConnection objeto .
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 objeto creado OdbcCommandanteriormente, OdbcCommand no se clona. En su lugar, mantiene SelectCommand una referencia al objeto creado OdbcCommand anteriormente.
Si SelectCommand no devuelve ninguna fila, no se agregan tablas a DataSety no se genera ninguna excepción.