Create a Data Access Object for Teradata Data using JDBI

JDBI is a SQL convenience library for Java that exposes two different style APIs, a fluent style and a SQL object style. The CData JDBC Driver for Teradata integrates connectivity to live Teradata data in Java applications. By pairing these technologies, you gain simple, programmatic access to Teradata data. This article explains how to build a basic Data Access Object (DAO) and the accompanying code to read and write Teradata data.

Create a DAO for the Teradata NorthwindProducts Entity

The interface below declares the desired behavior for the SQL object to create a single method for each SQL statement to be implemented.

public interface MyNorthwindProductsDAO {
 //insert new data into Teradata
 @SqlUpdate("INSERT INTO NorthwindProducts (CategoryId, ProductName) values (:categoryId, :productName)")
 void insert(@Bind("categoryId") String categoryId, @Bind("productName") String productName);

 //request specific data from Teradata (String type is used for simplicity)
 @SqlQuery("SELECT ProductName FROM NorthwindProducts WHERE CategoryId = :categoryId")
 String findProductNameByCategoryId(@Bind("categoryId") String categoryId);

 /*
 * close with no args is used to close the connection
 */
 void close();
}

Open a Connection to Teradata

Collect the necessary connection properties and construct the appropriate JDBC URL for connecting to Teradata.

To connect to Teradata, provide authentication information and specify the database server name.

• User: Set this to the username of a Teradata user.
• Password: Set this to the password of the Teradata user.
• DataSource: Specify the Teradata server name, DBC Name, or TDPID.
• Port: Specify the port the server is running on.
• Database: Specify the database name. If not specified, the default database is used.

Built-in Connection String Designer

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

java -jar cdata.jdbc.teradata.jar

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

A connection string for Teradata will typically look like the following:

jdbc:teradata:User=myuser;Password=mypassword;Server=localhost;Database=mydatabase;

Use the configured JDBC URL to obtain an instance of the DAO interface. The particular method shown below will open a handle bound to the instance, so the instance needs to be closed explicitly to release the handle and the bound JDBC connection.

DBI dbi = new DBI("jdbc:teradata:User=myuser;Password=mypassword;Server=localhost;Database=mydatabase;");
MyNorthwindProductsDAO dao = dbi.open(MyNorthwindProductsDAO.class);

//do stuff with the DAO

dao.close();

Read Teradata Data

With the connection open to Teradata, simply call the previously defined method to retrieve data from the NorthwindProducts entity in Teradata.

//disply the result of our 'find' method
String productName = dao.findProductNameByCategoryId("5");
System.out.println(productName);

Write Teradata Data

It is also simple to write data to Teradata, using the previously defined method.

//add a new entry to the NorthwindProducts entity
dao.insert(newCategoryId, newProductName);

Since the JDBI library is able to work with JDBC connections, you can easily produce a SQL Object API for Teradata by integrating with the CData JDBC Driver for Teradata. Download a free trial and work with live Teradata data in custom Java applications today.