OdbcDataAdapter Class

The OdbcDataAdapter serves as a bridge between a DataSet and data source for retrieving and saving data. The OdbcDataAdapter provides this bridge by using Fill to load data from the data source into the DataSet, and using Update to send changes made in the DataSet back to the data source.

When the OdbcDataAdapter fills a DataSet, it creates the required tables and columns for the returned data if they do not already exist. However, primary key information is not included in the implicitly created schema unless the MissingSchemaAction property is set to AddWithKey. You may also have the OdbcDataAdapter create the schema of the DataSet, including primary key information, before filling it with data using FillSchema. For more information, see Adding Existing Constraints to a DataSet (ADO.NET).

Note

When you call the Fill method on a data source that does not have a primary key column, the OdbcDataAdapter tries to promote the unique constraint column to the primary key. In the process, the OdbcDataAdapter marks the unique constraint as not nullable. This behavior works unless there is a null value in the unique constraint column. If there is a null value, the Fill method fails with a constraint violation. To avoid this situation, do not allow null values in the unique constraint column.

Note
Due to the limitations of native ODBC drivers, only one DataTable is ever returned when you call FillSchema. This is true even when executing SQL batch statements from which multiple DataTable objects would be expected.

The OdbcDataAdapter also includes the SelectCommand, InsertCommand, DeleteCommand, UpdateCommand, and TableMappings properties to facilitate loading and updating of data.

The following example uses OdbcCommand, OdbcDataAdapter, and OdbcConnection to select records and populate a DataSet with the selected rows.

public DataSet GetDataSetFromAdapter(
    DataSet dataSet, string connectionString, string queryString)
{
    using (OdbcConnection connection = 
               new OdbcConnection(connectionString))
    {
        OdbcDataAdapter adapter = 
            new OdbcDataAdapter(queryString, connection);

        // Open the connection and fill the DataSet.
        try
        {
            connection.Open();
            adapter.Fill(dataSet);
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.Message);
        }
        // The connection is automatically closed when the
        // code exits the using block.
    }
    return dataSet;
}

.NET Framework

.NET Framework Client Profile

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference

Other Resources