Sql from inside Hive UDF

Question

Is it possible to execute a Sql on Hive itself from inside a Hive UDF? I tried doing it using below snippet:

        Class.forName("org.apache.hadoop.hive.jdbc.HiveDriver");

        Connection con = DriverManager.getConnection("jdbc:hive://localhost:10000/default", "", "");

but this gave me a connection refused error, whereas I am able to telnet to the port from machine itself.

Answer 1

Hive UDFs are executed on the task nodes. Unless you're running hive server on every task node (hopefully not), giving the connection URL as "localhost:10000" will not work. You must give it the actual address of the hive server node, whether that is an actual name (e.g. my-hive-server-node.company.com:10000) or just an ip (e.g. 10.20.30.40:10000).

Also, I would really take a step back and make sure this is really what you want to do. This seems like it's really against the intentions of Hive.