Connect to FTP Data as a Linked Server

You can use CData Connect to set up a linked server for FTP data. After you configure CData Connect, you can use the UI in SQL Server Management Studio or call stored procedures to create the linked server. You can then work with FTP data just as you would a linked SQL Server instance.

CData Connect provides a pure SQL interface for FTP, allowing you to easily integrate with live FTP data in SQL Server — without replicating the data. Connect looks exactly like another SQL Server database and uses optimized data processing out of the box to push all supported SQL operations (filters, JOINs, etc) directly to FTP, leveraging server-side processing to quickly return FTP data.

Create a Virtual SQL Database for FTP Data

CData Connect Server uses a straightforward, point-and-click interface to connect to data sources and generate APIs.

1. Log into Connect Server and click Connections.
2. Select "FTP" from Available Data Sources.
3. Enter the necessary authentication properties to connect to FTP.

   To connect to FTP or SFTP servers, specify at least RemoteHost and FileProtocol. Specify the port with RemotePort.

   Set User and Password to perform Basic authentication. Set SSHAuthMode to use SSH authentication. See the Getting Started section of the data provider help documentation for more information on authenticating via SSH.

   Set SSLMode and SSLServerCert to secure connections with SSL.

   The data provider lists the tables based on the available folders in your FTP server. Set the following connection properties to control the relational view of the file system:

   • RemotePath: Set this to the current working directory.
   • TableDepth: Set this to control the depth of folders to list as views.
   • FileRetrievalDepth: Set this to retrieve and list files recursively from the root table.

   Stored Procedures are available to download files, upload files, and send protocol commands. See the Data Model chapter of the FTP data provider documentation for more information.

4. Click Save Changes
5. Click Privileges -> Add and add the new user (or an existing user) with the appropriate permissions.

Create a Linked Server for FTP Data

After you have configured and started the daemon, create the linked server and connect. You can use the UI in SQL Server Management Studio or call stored procedures.

Create a Linked Server from the UI

Follow the steps below to create a linked server from the Object Explorer.

1. Open SQL Server Management Studio and connect to an instance of SQL Server.
2. In the Object Explorer, expand the node for the SQL Server database. In the Server Objects node, right-click Linked Servers and click New Linked Server. The New Linked Server dialog is displayed.
3. In the General section, click the Other Data Source option and enter the following information after naming the linked server:
   • Provider: Select the SQL Server Native Client Provider that corresponds to your version of SQL Server. For example, SQL Server Native Client 11.0.

   • Data Source: Enter the host and port, separated by a comma, where the TDS remoting service is running.

     Note that a value of "localhost" in this input refers to the machine where SQL Server is running, so be careful if you create a linked server in Management Studio on a different machine.

   • Catalog: Enter the CData system DSN, CData FTP Sys.
4. In the Security section, select the option to have the connection "made using this security context" and enter the username and password of a user you created in the Users tab of the SQL Gateway.

Create a Linked Server Programmatically

In addition to using the SQL Server Management Studio UI to create a linked server, you can use stored procedures. The following inputs are required:

• server: The linked server name.
• provider: Enter "SQLNCLI" for the SQL Server Native Client Provider.

• datasrc: The host and port, separated by a comma, where the service is running.

  Note that a value of "localhost" in the datasrc input refers to the machine where SQL Server is running, so be careful if you create a linked server in Management Studio on a different machine.

• catalog: Leave this empty.
• srvproduct: Enter the product name of the data source; this can be an arbitrary value like "CData Connect" or an empty string.

Follow the steps below to create the linked server and configure authentication to the SQL Gateway:

1. Call sp_addlinkedserver to create the linked server:

   EXEC sp_addlinkedserver @server='CDataConnect', @provider='SQLNCLI', @datasrc='< MachineIPAddress >,1434', @catalog='', @srvproduct=''; GO

2. Call the sp_addlinkedsrvlogin stored procedure to allow SQL Server users to connect with the credentials of an authorized user of the service. Note that the credentials you use to connect to the service must specify a user you configured on the Users tab of the SQL Gateway.

   EXEC sp_addlinkedsrvlogin @rmtsrvname='CDataConnect', @rmtuser='< CData Connect user >', @rmtpassword='< CData Connect password >', @useself='FALSE', @locallogin=NULL; GO

Connect from SQL Server Management Studio

Since CData Connect provides a virtual SQL Server interface, there is no further configuration needed to work with your FTP data directly from SQL Server. Simply execute queries against CData Connect just like you would any other Linked Server.

Execute Queries

You can now execute queries to the FTP linked server from any tool that can connect to SQL Server. Set the table name accordingly:

SQL Access to FTP Data

At this point, you have a direct connection to live FTP data from your SQL Server instance. You can work with live FTP data just like you would any other SQL Server database, with no need to replicate the data. For more information on gaining SQL access to data from more than 100 SaaS, Big Data, and NoSQL sources, refer to our CData Connect page.