How do I make an async call to Hive in Java?

[Peter Sankauskas <pe...@motally.com>]

Hi everyone,

I would like to execute a Hive query on the server in an asynchronous
manner. The Hive query will likely take a long time to complete, so I would
prefer not to block on the call. I am currently using Thirft to make a
blocking call (blocks on client.execute()), but I have not seen an example
of how to make a non-blocking call. Here is the blocking code:

    TSocket transport = new TSocket("hive.example.com", 10000);
    transport.setTimeout(999999999);
    TBinaryProtocol protocol = new TBinaryProtocol(transport);
    Client client = new ThriftHive.Client(protocol);
    transport.open();
    client.execute(hql);  // Omitted HQL

    List<String> rows;
    while ((rows = client.fetchN(1000)) != null) {
        for (String row : rows) {
            // Do stuff with row
        }
    }

    transport.close();

The code above is missing try/catch blocks to keep it short.

I can see that Thirft has things like "TNonblockingSocket" but I cannot find
any examples of how to use it, or if Hive even supports it. Does anyone have
any ideas how to do an async call? Is there a better way?

Thanks!

Kind regards,
Peter Sankauskas

Re: How do I make an async call to Hive in Java?

[Zheng Shao <zs...@gmail.com>]

Hi Peter,

Currently there is no such method in Hive. It should be pretty
straightforward to do it with a thread.
I would encourage you to open a JIRA and post a patch if you are
interested in making it work.

Zheng

On Tue, Feb 2, 2010 at 9:42 AM, Peter Sankauskas <pe...@motally.com> wrote:
> Hi everyone,
>
> I would like to execute a Hive query on the server in an asynchronous
> manner. The Hive query will likely take a long time to complete, so I would
> prefer not to block on the call. I am currently using Thirft to make a
> blocking call (blocks on client.execute()), but I have not seen an example
> of how to make a non-blocking call. Here is the blocking code:
>
>     TSocket transport = new TSocket("hive.example.com", 10000);
>     transport.setTimeout(999999999);
>     TBinaryProtocol protocol = new TBinaryProtocol(transport);
>     Client client = new ThriftHive.Client(protocol);
>     transport.open();
>     client.execute(hql);  // Omitted HQL
>
>     List<String> rows;
>     while ((rows = client.fetchN(1000)) != null) {
>         for (String row : rows) {
>             // Do stuff with row
>         }
>     }
>
>     transport.close();
>
> The code above is missing try/catch blocks to keep it short.
>
> I can see that Thirft has things like "TNonblockingSocket" but I cannot find
> any examples of how to use it, or if Hive even supports it. Does anyone have
> any ideas how to do an async call? Is there a better way?
>
> Thanks!
>
> Kind regards,
> Peter Sankauskas
>



-- 
Yours,
Zheng