Added TPCH query examples for Scala API

Improved Java TPCH query examples
Removed RelationalQuery Java API example

flink-examples/flink-java-examples/src/main/java/org/apache/flink/examples/java/relational/TPCHQuery10.java

@@ -104,13 +104,10 @@ public static void main(String[] args) throws Exception {
 
  // get customer data set: (custkey, name, address, nationkey, acctbal) 
  DataSet<Tuple5<Integer, String, String, Integer, Double>> customers = getCustomerDataSet(env);
-
  // get orders data set: (orderkey, custkey, orderdate)
  DataSet<Tuple3<Integer, Integer, String>> orders = getOrdersDataSet(env);
-
  // get lineitem data set: (orderkey, extendedprice, discount, returnflag)
  DataSet<Tuple4<Integer, Double, Double, String>> lineitems = getLineitemDataSet(env);
-
  // get nation data set: (nationkey, name)
  DataSet<Tuple2<Integer, String>> nations = getNationsDataSet(env);
 
@@ -120,46 +117,38 @@ public static void main(String[] args) throws Exception {
  orders.filter(
  new FilterFunction<Tuple3<Integer,Integer, String>>() {
  @Override
- public boolean filter(Tuple3<Integer, Integer, String> t) {
- int year = Integer.parseInt(t.f2.substring(0, 4));
- return year > 1990;
+ public boolean filter(Tuple3<Integer, Integer, String> o) {
+ return Integer.parseInt(o.f2.substring(0, 4)) > 1990;
  }
  })
  // project fields out that are no longer required
  .project(0,1).types(Integer.class, Integer.class);
 
- // lineitems filtered by flag: (orderkey, extendedprice, discount)
- DataSet<Tuple3<Integer, Double, Double>> lineitemsFilteredByFlag = 
+ // lineitems filtered by flag: (orderkey, revenue)
+ DataSet<Tuple2<Integer, Double>> lineitemsFilteredByFlag = 
  // filter by flag
  lineitems.filter(new FilterFunction<Tuple4<Integer, Double, Double, String>>() {
  @Override
- public boolean filter(Tuple4<Integer, Double, Double, String> t)
- throws Exception {
- return t.f3.equals("R");
+ public boolean filter(Tuple4<Integer, Double, Double, String> l) {
+ return l.f3.equals("R");
  }
  })
- // project fields out that are no longer required
- .project(0,1,2).types(Integer.class, Double.class, Double.class);
-
- // join orders with lineitems: (custkey, extendedprice, discount)
- DataSet<Tuple3<Integer, Double, Double>> lineitemsOfCustomerKey = 
- ordersFilteredByYear.joinWithHuge(lineitemsFilteredByFlag)
- .where(0).equalTo(0)
- .projectFirst(1).projectSecond(1,2)
- .types(Integer.class, Double.class, Double.class);
-
- // aggregate for revenue: (custkey, revenue)
- DataSet<Tuple2<Integer, Double>> revenueOfCustomerKey = lineitemsOfCustomerKey
- // calculate the revenue for each item
- .map(new MapFunction<Tuple3<Integer, Double, Double>, Tuple2<Integer, Double>>() {
+ // compute revenue and project out return flag
+ .map(new MapFunction<Tuple4<Integer, Double, Double, String>, Tuple2<Integer, Double>>() {
  @Override
- public Tuple2<Integer, Double> map(Tuple3<Integer, Double, Double> t) {
+ public Tuple2<Integer, Double> map(Tuple4<Integer, Double, Double, String> l) {
  // revenue per item = l_extendedprice * (1 - l_discount)
- return new Tuple2<Integer, Double>(t.f0, t.f1 * (1 - t.f2));
+ return new Tuple2<Integer, Double>(l.f0, l.f1 * (1 - l.f2));
  }
- })
- // aggregate the revenues per item to revenue per customer
- .groupBy(0).aggregate(Aggregations.SUM, 1);
+ });
+
+ // join orders with lineitems: (custkey, revenue)
+ DataSet<Tuple2<Integer, Double>> revenueByCustomer = 
+ ordersFilteredByYear.joinWithHuge(lineitemsFilteredByFlag)
+ .where(0).equalTo(0)
+ .projectFirst(1).projectSecond(1)
+ .types(Integer.class, Double.class)
+ .groupBy(0).aggregate(Aggregations.SUM, 1);
 
  // join customer with nation (custkey, name, address, nationname, acctbal)
  DataSet<Tuple5<Integer, String, String, String, Double>> customerWithNation = customers
@@ -169,14 +158,14 @@ public Tuple2<Integer, Double> map(Tuple3<Integer, Double, Double> t) {
  .types(Integer.class, String.class, String.class, String.class, Double.class);
 
  // join customer (with nation) with revenue (custkey, name, address, nationname, acctbal, revenue)
- DataSet<Tuple6<Integer, String, String, String, Double, Double>> customerWithRevenue = 
- customerWithNation.join(revenueOfCustomerKey)
+ DataSet<Tuple6<Integer, String, String, String, Double, Double>> result = 
+ customerWithNation.join(revenueByCustomer)
  .where(0).equalTo(0)
  .projectFirst(0,1,2,3,4).projectSecond(1)
  .types(Integer.class, String.class, String.class, String.class, Double.class, Double.class);
 
  // emit result
- customerWithRevenue.writeAsCsv(outputPath);
+ result.writeAsCsv(outputPath, "\n", "|");
 
  // execute program
  env.execute("TPCH Query 10 Example");