IMPALA-2015: Add support for nested loop join

Implement nested-loop join in Impala with support for multiple join
modes, including inner, outer, semi and anti joins. Null-aware left
anti-join is not currently supported.

Summary of changes:
Introduced the NestedLoopJoinNode class in the FE that represents the nested
loop join. Common functionality between NestedLoopJoinNode and HashJoinNode
(e.g. cardinality estimation) was moved to the JoinNode class.
In the BE, introduced the NestedLoopJoinNode class that implements the nested-loop
join execution strategy.

Change-Id: I238ec7dc0080f661847e5e1b84e30d61c3b0bb5c
Reviewed-on: http://gerrit.cloudera.org:8080/652
Reviewed-by: Dimitris Tsirogiannis <dtsirogiannis@cloudera.com>
Tested-by: Internal Jenkins

be/src/exec/CMakeLists.txt

@@ -28,7 +28,6 @@ add_library(Exec
   base-sequence-scanner.cc
   blocking-join-node.cc
   catalog-op-executor.cc
-  cross-join-node.cc
   data-sink.cc
   data-source-scan-node.cc
   delimited-text-parser.cc
@@ -61,6 +60,7 @@ add_library(Exec
   hbase-scan-node.cc
   hbase-table-scanner.cc
   incr-stats-util.cc
+  nested-loop-join-node.cc
   partitioned-aggregation-node.cc
   partitioned-aggregation-node-ir.cc
   partitioned-hash-join-node.cc
@@ -88,4 +88,4 @@ ADD_BE_TEST(read-write-util-test)
 ADD_BE_TEST(parquet-plain-test)
 ADD_BE_TEST(parquet-version-test)
 ADD_BE_TEST(row-batch-list-test)
-ADD_BE_TEST(incr-stats-util-test)
+ADD_BE_TEST(incr-stats-util-test)

be/src/exec/blocking-join-node.cc

@@ -38,12 +38,17 @@ BlockingJoinNode::BlockingJoinNode(const string& node_name, const TJoinOp::type
     join_op_(join_op),
     eos_(false),
     probe_side_eos_(false),
+    probe_batch_pos_(-1),
+    current_probe_row_(NULL),
     semi_join_staging_row_(NULL),
     can_add_probe_filters_(false) {
 }
 
 Status BlockingJoinNode::Init(const TPlanNode& tnode) {
   RETURN_IF_ERROR(ExecNode::Init(tnode));
+  DCHECK((join_op_ != TJoinOp::LEFT_SEMI_JOIN && join_op_ != TJoinOp::LEFT_ANTI_JOIN &&
+      join_op_ != TJoinOp::RIGHT_SEMI_JOIN && join_op_ != TJoinOp::RIGHT_ANTI_JOIN &&
+      join_op_ != TJoinOp::NULL_AWARE_LEFT_ANTI_JOIN) || conjunct_ctxs_.size() == 0);
   return Status::OK();
 }
 

be/src/exec/exec-node.cc

@@ -26,13 +26,13 @@
 #include "exprs/expr.h"
 #include "exec/aggregation-node.h"
 #include "exec/analytic-eval-node.h"
-#include "exec/cross-join-node.h"
 #include "exec/data-source-scan-node.h"
 #include "exec/empty-set-node.h"
 #include "exec/exchange-node.h"
 #include "exec/hash-join-node.h"
 #include "exec/hbase-scan-node.h"
 #include "exec/hdfs-scan-node.h"
+#include "exec/nested-loop-join-node.h"
 #include "exec/partitioned-aggregation-node.h"
 #include "exec/partitioned-hash-join-node.h"
 #include "exec/select-node.h"
@@ -299,8 +299,8 @@ Status ExecNode::CreateNode(ObjectPool* pool, const TPlanNode& tnode,
         *node = pool->Add(new HashJoinNode(pool, tnode, descs));
       }
       break;
-    case TPlanNodeType::CROSS_JOIN_NODE:
-      *node = pool->Add(new CrossJoinNode(pool, tnode, descs));
+    case TPlanNodeType::NESTED_LOOP_JOIN_NODE:
+      *node = pool->Add(new NestedLoopJoinNode(pool, tnode, descs));
       break;
     case TPlanNodeType::EMPTY_SET_NODE:
       *node = pool->Add(new EmptySetNode(pool, tnode, descs));