Connect to Presto Data in CloverDX (formerly CloverETL)

The CData JDBC Driver for Presto enables you to use the data transformation components in CloverDX (formerly CloverETL) to work with Presto as sources and destinations. In this article, you will use the JDBC Driver for Presto to set up a simple transfer into a flat file. The CData JDBC Driver for Presto enables you to use the data transformation components in CloverDX (formerly CloverETL) to work with Presto as sources and destinations. In this article, you will use the JDBC Driver for Presto to set up a simple transfer into a flat file.

Getting Started

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Connect to Presto as a JDBC Data Source

1. Create the connection to Presto data. In a new CloverDX graph, right-click the Connections node in the Outline pane and click Connections -> Create Connection. The Database Connection wizard is displayed.
2. Click the plus icon to load a driver from a JAR. Browse to the lib subfolder of the installation directory and select the cdata.jdbc.presto.jar file.
3. Enter the JDBC URL.

   Set the Server and Port connection properties to connect, in addition to any authentication properties that may be required.

   To enable TLS/SSL, set UseSSL to true.

   Authenticating with LDAP

   In order to authenticate with LDAP, set the following connection properties:

   • AuthScheme: Set this to LDAP.
   • User: The username being authenticated with in LDAP.
   • Password: The password associated with the User you are authenticating against LDAP with.

   Authenticating with Kerberos

   In order to authenticate with KERBEROS, set the following connection properties:

   • AuthScheme: Set this to KERBEROS.
   • KerberosKDC: The Kerberos Key Distribution Center (KDC) service used to authenticate the user.
   • KerberosRealm: The Kerberos Realm used to authenticate the user with.
   • KerberosSPN: The Service Principal Name for the Kerberos Domain Controller.
   • KerberosKeytabFile: The Keytab file containing your pairs of Kerberos principals and encrypted keys.
   • User: The user who is authenticating to Kerberos.
   • Password: The password used to authenticate to Kerberos.

   Built-in Connection String Designer

   For assistance in constructing the JDBC URL, use the connection string designer built into the Presto JDBC Driver. Either double-click the JAR file or execute the jar file from the command-line.

   java -jar cdata.jdbc.presto.jar

   Fill in the connection properties and copy the connection string to the clipboard.

   

   A typical JDBC URL is below:

   jdbc:presto:Server=127.0.0.1;Port=8080;

Query Presto Data with the DBInputTable Component

1. Drag a DBInputTable from the Readers selection of the Palette onto the job flow and double-click it to open the configuration editor.
2. In the DB connection property, select the Presto JDBC data source from the drop-down menu.
3. Enter the SQL query. For example: SELECT FirstName, LastName FROM Customer WHERE Id = '123456789'

Write the Output of the Query to a UniversalDataWriter

1. Drag a UniversalDataWriter from the Writers selection onto the jobflow.
2. Double-click the UniversalDataWriter to open the configuration editor and add a file URL.
3. Right-click the DBInputTable and then click Extract Metadata.
4. Connect the output port of the DBInputTable to the UniversalDataWriter.
5. In the resulting Select Metadata menu for the UniversalDataWriter, choose the Customer table. (You can also open this menu by right-clicking the input port for the UniversalDataWriter.)
6. Click Run to write to the file.