You can use the SELECT INTO statement to export formatted data to a file.

Data Export with an SQL Query

The following query exports data into a file formatted in comma-separated values (CSV):

SELECT Id, Name INTO [csv://\"CData\".\"Sample\".Products.txt] FROM [\"CData\".\"Sample\".Products] WHERE Industry = 'Floppy Disks'

You can specify other formats in the file URI. The possible delimiters are tab, semicolon, and comma with the default being a comma. The following example exports tab-separated values:

SELECT Id, Name INTO [csv://\"CData\".\"Sample\".Products.txt;delimiter=tab] FROM ["CData"."Sample".Products] WHERE Industry = 'Floppy Disks'

C#

String connectionString = "Database=MyCassandraDB;Port=9042;Server=127.0.0.1;";

using (CassandraConnection connection = new CassandraConnection(connectionString)) {
  CassandraCommand cmd = new CassandraCommand("SELECT Id, Name INTO [csv://\"CData\".\"Sample\".Products.txt] FROM [\"CData\".\"Sample\".Products] WHERE Industry = 'Floppy Disks' ", connection);
  int rowsAffected = cmd.ExecuteNonQuery();
} 

VB.NET

Dim connectionString As [String] = "Database=MyCassandraDB;Port=9042;Server=127.0.0.1;" 

Using connection As New CassandraConnection(connectionString)
  Dim cmd As New CassandraCommand("SELECT Id, Name INTO [csv://\"CData\".\"Sample\".Products.txt] FROM [\"CData\".\"Sample\".Products] WHERE Industry = 'Floppy Disks'", connection)
  Dim rowsAffected As Integer = cmd.ExecuteNonQuery()
End Using

You can specify other file formats in the URI. The following example exports tab-separated values:

C#

String connectionString = "Database=MyCassandraDB;Port=9042;Server=127.0.0.1;";

using (CassandraConnection connection = new CassandraConnection(connectionString)) {
  CassandraCommand cmd = new CassandraCommand("SELECT * INTO [\"CData\".\"Sample\".Products] IN [csv://filename=c:/\"CData\".\"Sample\".Products.csv;delimiter=tab] FROM [\"CData\".\"Sample\".Products] WHERE Industry = 'Floppy Disks'", connection);
  int rowsAffected = cmd.ExecuteNonQuery();
} 

VB.NET

Dim connectionString As [String] = "Database=MyCassandraDB;Port=9042;Server=127.0.0.1;" 

Using connection As New CassandraConnection(connectionString)
  Dim cmd As New CassandraCommand("SELECT * INTO [\"CData\".\"Sample\".Products] IN [csv://filename=c:/\"CData\".\"Sample\".Products.csv;delimiter=tab] FROM [\"CData\".\"Sample\".Products] WHERE Industry = 'Floppy Disks'", connection)
  Dim rowsAffected As Integer = cmd.ExecuteNonQuery()
End Using