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From Haoming Zhang <haoming.zh...@outlook.com>
Subject RE: SPARKSQL problem with implementing Scala's Product interface
Date Thu, 10 Jul 2014 18:33:51 GMT
Hi Yadid,

I have the same problem with you so I implemented the product interface as well, even the
codes are similar with your codes. But now I face another problem that is I don't know how
to run the codes...My whole program is like this:

object SimpleApp {

  class Record(val x1: String, val x2: String, val x3: String, ... val x24: String) extends
Product with Serializable {
    def canEqual(that: Any) = that.isInstanceOf[Record]

    def productArity = 24

    def productElement(n: Int) = n match {
      case 0 => x1
      case 1 => x2
      case 2 => x3
      ...
      case 23 => x24
    }
  }
  
  def main(args: Array[String]) {

    val conf = new SparkConf().setAppName("Product Test")
    val sc = new SparkContext(conf)
    val sqlContext = new SQLContext(sc);

    val record = new Record("a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m",
"n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x")

    import sqlContext._
    sc.parallelize(record :: Nil).registerAsTable("records")

    sql("SELECT x1 FROM records").collect()
  }
}

I tried to run the above program with spark-submit: 
./spark-submit --class "SimpleApp" --master local /playground/ProductInterface/target/scala-2.10/classes/product-interface-test_2.10-1.0.jar

But I always get the exception that is "Exception in thread "main" java.lang.ClassNotFoundException:
SimpleApp".

So can you please share me the way to run the test program? Actually I can see there is a
SimpleApp.class in classes folder, but I don't understand why spark-submit cannot find it.

Best,
Haoming

> Date: Thu, 10 Jul 2014 09:02:18 -0700
> From: yadid@media.mit.edu
> To: user@spark.incubator.apache.org
> Subject: SPARKSQL problem with implementing Scala's Product interface
> 
> Hi All,
> 
> I have a class with too many variables to be implemented as a case class,
> therefor I am using regular class that implements Scala's product interface.
> Like so:
> 
> class Info () extends Product with Serializable {
>     var param1 : String = ""
>     var param2 : String = ""  
>   ...
>     var param38: String = ""
> 
>    def canEqual(that: Any) = that.isInstanceOf[Info]
>     def productArity = 38
>     def productElement(n: Int) = n match {
>          case 0 => param1
>          case 1 => param2
>          ...
>          case 37 => param38
>         }
> }
> 
> after registering the table as info when I execute "SELECT * from info" I
> get the expected result.
> However, when I execute "SELECT param1, param2 from info" I get the
> following exception:
> Loss was due to
> org.apache.spark.sql.catalyst.errors.package$TreeNodeException: No function
> to evaluate expression. type: UnresolvedAttribute, tree: 'param1
> 
> I guess I must be missing a method in the implementation. Any pointers
> appreciated.
> 
> Yadid
> 
> 
> 
> 
> 
> 
> 
> 
> --
> View this message in context: http://apache-spark-user-list.1001560.n3.nabble.com/SPARKSQL-problem-with-implementing-Scala-s-Product-interface-tp9311.html
> Sent from the Apache Spark User List mailing list archive at Nabble.com.
 		 	   		  
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