question Re: How to run spark sql in parallel? in Archives of Support Questions (Read Only)

How to run spark sql in parallel?

Kamalakanta — Fri, 16 Sep 2022 10:44:21 GMT

We are doing spark programming in java language. The ‘DataFrame’ has been stored in temporary table and we are running multiple queries from this temporary table inside loop. The quires are running in sequential order. We need to run in parallel from temporary table. Please find code snippet below.

Thanks in advance for your cooperation.

HiveContext hiveContext = new HiveContext(sparkContext);

String mainQueryHql = getFileContent(mainQueryFilePath);

DataFrame df = hiveContext.sql(mainQueryHql).persist(StorageLevel.MEMORY_AND_DISK_SER());

df.show();

System.out.println("Total Records in Main Query " + df.count());

df.registerTempTable(tempTable);

ArrayList<DataFrame> dataFrameList = new ArrayList();

DataFrame dfSubQuery = null;

String subQuires = getFileContent(subQueryFilePath);

String[] alQuires = subQuires.split(";");

for(int i=0; i<alQuires.length; i++) {

System.out.println("Query no " + i +" is : " + alQuires[i]);

logger.debug("Query no " + i +" is : " + alQuires[i]);

dfSubQuery = hiveContext.sql(alQuires[i]);

dfSubQuery.show();

dataFrameList.add(dfSubQuery);

}

Re: How to run spark sql in parallel?

hubbarja — Sun, 23 Oct 2016 02:26:29 GMT

There is nothing native within Spark to handle running queries in parallel. Instead you can take a look at Java concurrency and in particular Futures[1] which will allow you to start queries in parallel and check status later.

1. https://docs.oracle.com/javase/7/docs/api/java/util/concurrent/Future.html

Re: How to run spark sql in parallel?

Kamalakanta — Mon, 24 Oct 2016 10:10:27 GMT

Thanks Hubbarja, Will check and respond very shortly.

Re: How to run spark sql in parallel?

HadoopSiva — Tue, 22 Nov 2016 18:25:09 GMT

Hi Kamalakanta,

I am also in need of a solution for this problem.

Have you checked with Java Concurrency and Futures ? or else do u got any other solution?

Please share the solution.

I am also in need of executing the sparksql in parallel(similar to your program).

Thanks in advance

Re: How to run spark sql in parallel?

Kamalakanta — Wed, 23 Nov 2016 11:01:09 GMT

Please use Future interface in your code. Request to explorebelow mentioned object or interfaces.

java.util.concurrent.ExecutionException;
java.util.concurrent.ExecutorService;
java.util.concurrent.Executors;
java.util.concurrent.Future;

You can get more information from below mentioned URLs.

https://docs.oracle.com/javase/7/docs/api/java/util/concurrent/Future.html

Re: How to run spark sql in parallel?

Kamalakanta — Wed, 23 Nov 2016 11:04:46 GMT

One more helpfull link

http://stackoverflow.com/questions/28712420/how-to-run-concurrent-jobsactions-in-apache-spark-using-single-spark-context

Re: How to run spark sql in parallel?

HadoopSiva — Mon, 28 Nov 2016 12:54:56 GMT

It will be of great help to me.
Thanks a lot Kamalakanta 🙂

I have some more doubts regarding running spark SQL queries in parallel.