I am using Presto to query Hive tables in EMR. I initialized presto driver and get the connection, but when I am trying to execute a query on that connection, I am getting an error: Server refused connection: http://aws.address/v1/statement.
Do I need to set Hive/AWS credentials before using it? How can I do it?
public void init() {
try {
Class.forName("com.facebook.presto.jdbc.PrestoDriver");
if(connection == null)
connection = DriverManager.getConnection(url,username,password);
// url = "jdbc:presto://aws.address:8889/hive/default"
} catch (ClassNotFoundException | SQLException e) {
// TOD: handle exception
e.printStackTrace();
}
}
public void executeMyQuery() {
if(connection == null) {
connection = driver.getConnection();
}
ResultSet resultSet = null;
Statement stmt = connection.createStatement();
try {
resultSet = stmt.executeQuery(query);
} catch (Exception e) {
logger.error("Failed to execute query, with error: ",e);
} finally {
if(resultSet != null) {
try {
resultSet.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if(stmt != null){
stmt.close();
}
}
}
I needed to use 'port forwarding' command (ssh) in order to reach presto driver in AWS.