Tajo JDBC Driver¶

Apache Tajo™ provides JDBC driver which enables Java applciations to easily access Apache Tajo in a RDBMS-like manner. In this section, we explain how to get JDBC driver and an example code.

How to get JDBC driver¶

Direct Download¶

You can directly download a JDBC driver jar file (tajo-jdbc-x.y.z.jar) from Downloads.

From Binary Distribution¶

Tajo binary distribution provides JDBC jar file located in ${TAJO_HOME}/share/jdbc-dist/tajo-jdbc-x.y.z.jar.

From Building Source Code¶

You can build Tajo from the source code and then get JAR files as follows:

$ tar xzvf tajo-x.y.z-src.tar.gz
$ mvn clean package -DskipTests -Pdist -Dtar
$ ls -l tajo-dist/target/tajo-x.y.z/share/jdbc-dist/tajo-jdbc-x.y.z.jar

Setting the CLASSPATH¶

In order to use the JDBC driver, you should add tajo-jdbc-x.y.z.jar in your CLASSPATH.

CLASSPATH=path/to/tajo-jdbc-x.y.z.jar:$CLASSPATH

An Example JDBC Client¶

The JDBC driver class name is org.apache.tajo.jdbc.TajoDriver. You can get the driver Class.forName("org.apache.tajo.jdbc.TajoDriver"). The connection url should be jdbc:tajo://<TajoMaster hostname>:<TajoMaster client rpc port>/<database name>. The default TajoMaster client rpc port is 26002. If you want to change the listening port, please refer Cluster Setup.

Note

Currently, Tajo does not support the concept of database and namespace. All tables are contained in default database. So, you don’t need to specify any database name.

The following shows an example of JDBC Client.

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.Statement;
import java.sql.DriverManager;

public class TajoJDBCClient {

  ....

  public static void main(String[] args) throws Exception {

    try {
      Class.forName("org.apache.tajo.jdbc.TajoDriver");
    } catch (ClassNotFoundException e) {
      // fill your handling code
    }

    Connection conn = DriverManager.getConnection("jdbc:tajo://127.0.0.1:26002/default");

    Statement stmt = null;
    ResultSet rs = null;
    try {
      stmt = conn.createStatement();
      rs = stmt.executeQuery("select * from table1");
      while (rs.next()) {
        System.out.println(rs.getString(1) + "," + rs.getString(3));
      }
    } finally {
      if (rs != null) rs.close();
      if (stmt != null) stmt.close();
      if (conn != null) conn.close();
    }
  }
}