ADO.NET Provider for Amazon Athena

Build 23.0.8839

Querying with the DataReader

The CData ADO.NET Provider for Amazon Athena implements two ADO.NET interfaces you can use to retrieve data from Amazon Athena: AmazonAthenaDataAdapter and AmazonAthenaDataReader objects. Whereas AmazonAthenaDataAdapter objects retrieve a single result set of all the data that matches a query, AmazonAthenaDataReader objects fetch data in subset increments as needed.

Using the AmazonAthenaDataReader

The AmazonAthenaDataReader retrieves data faster than the AmazonAthenaDataAdapter because it can retrieve data in pages. As you read data from the AmazonAthenaDataReader, it periodically requests the next page of results from the data source, if required. This causes results to be returned at a faster rate. The following example selects all the columns from the [AwsDataCatalog].[sampledb].Customers table:

C#

string connectionString = "AWSAccessKey='a123';AWSSecretKey='s123';AWSRegion='IRELAND';Database='sampledb';S3StagingDirectory='s3://bucket/staging/';";

using (AmazonAthenaConnection connection = new AmazonAthenaConnection(connectionString)) {
  AmazonAthenaCommand cmd = new AmazonAthenaCommand("SELECT * FROM [AwsDataCatalog].[sampledb].Customers", connection);
  
  AmazonAthenaDataReader rdr = cmd.ExecuteReader();

  while (rdr.Read()) {
    Console.WriteLine(String.Format("\t{0} --> \t\t{1}", rdr["Name"], rdr["TotalDue"]));
  }
}

VB.NET

Dim connectionString As String = "AWSAccessKey='a123';AWSSecretKey='s123';AWSRegion='IRELAND';Database='sampledb';S3StagingDirectory='s3://bucket/staging/';"

Using connection As New AmazonAthenaConnection(connectionString)
  Dim cmd As New AmazonAthenaCommand("SELECT * FROM [AwsDataCatalog].[sampledb].Customers", connection)

  Dim rdr As AmazonAthenaDataReader = cmd.ExecuteReader()

  While rdr.Read()
    Console.WriteLine([String].Format(vbTab & "{0} --> " & vbTab & vbTab & "{1}", rdr("Name"), rdr("TotalDue")))
  End While
End Using

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Build 23.0.8839