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://Channels.txt] FROM [Channels] WHERE IsPublic = 'True'

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://Channels.txt;delimiter=tab] FROM [Channels] WHERE IsPublic = 'True'

C#

String connectionString = "";

using (SlackConnection connection = new SlackConnection(connectionString)) {
  SlackCommand cmd = new SlackCommand("SELECT Id, Name INTO [csv://Channels.txt] FROM [Channels] WHERE IsPublic = 'True' ", connection);
  int rowsAffected = cmd.ExecuteNonQuery();
} 

VB.NET

Dim connectionString As [String] = "" 

Using connection As New SlackConnection(connectionString)
  Dim cmd As New SlackCommand("SELECT Id, Name INTO [csv://Channels.txt] FROM [Channels] WHERE IsPublic = 'True'", 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 = "";

using (SlackConnection connection = new SlackConnection(connectionString)) {
  SlackCommand cmd = new SlackCommand("SELECT * INTO [Channels] IN [csv://filename=c:/Channels.csv;delimiter=tab] FROM [Channels] WHERE IsPublic = 'True'", connection);
  int rowsAffected = cmd.ExecuteNonQuery();
} 

VB.NET

Dim connectionString As [String] = "" 

Using connection As New SlackConnection(connectionString)
  Dim cmd As New SlackCommand("SELECT * INTO [Channels] IN [csv://filename=c:/Channels.csv;delimiter=tab] FROM [Channels] WHERE IsPublic = 'True'", connection)
  Dim rowsAffected As Integer = cmd.ExecuteNonQuery()
End Using