From 57dadf50ee4710c66da526b06a8cda0ba3aa9edd Mon Sep 17 00:00:00 2001
From: Collapsar <baofengqi@actionsky.com>
Date: Fri, 27 Nov 2020 22:32:44 +0800
Subject: [PATCH] optimize er left join global (#2334)

* optimize er left join global

* optimize er left join global

* fix checkstyle

(cherry picked from commit 2f6b3bfec14854e8e24b7a1f9d0e299a2c52fe55)
---
 dble_checkstyle_suppression.xml                           | 2 +-
 .../com/actiontech/dble/plan/optimizer/ERJoinChooser.java | 8 +++++---
 .../dble/plan/optimizer/GlobalTableProcessor.java         | 7 ++++---
 3 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/dble_checkstyle_suppression.xml b/dble_checkstyle_suppression.xml
index f9426b83b..e2ef88778 100644
--- a/dble_checkstyle_suppression.xml
+++ b/dble_checkstyle_suppression.xml
@@ -10,7 +10,6 @@
         "http://checkstyle.sourceforge.net/dtds/suppressions_1_1.dtd">
 
 <suppressions>
-    <suppress checks=".*" files="StructureMeta.java"/>
     <suppress checks=".*" files="UcoreInterface.java"/>
     <suppress checks=".*" files="UcoreGrpc.java"/>
     <suppress checks=".*" files="AlertBlockQueue.java"/>
@@ -24,6 +23,7 @@
     <suppress checks=".*" files="BTraceCostTime.java"/>
     <suppress checks="CyclomaticComplexity" files="CreateTableParserImp.java"/>
     <suppress checks="CyclomaticComplexity" files="XMLSchemaLoader.java"/>
+    <suppress checks="CyclomaticComplexity" files="GlobalTableProcessor.java"/>
     <suppress checks="UncommentedMain" files="XmltoCluster.java"/>
     <suppress checks="UncommentedMain" files="XmltoZkMain.java"/>
 </suppressions>
\ No newline at end of file
diff --git a/src/main/java/com/actiontech/dble/plan/optimizer/ERJoinChooser.java b/src/main/java/com/actiontech/dble/plan/optimizer/ERJoinChooser.java
index 96a294529..dd799a14b 100644
--- a/src/main/java/com/actiontech/dble/plan/optimizer/ERJoinChooser.java
+++ b/src/main/java/com/actiontech/dble/plan/optimizer/ERJoinChooser.java
@@ -77,7 +77,7 @@ public class ERJoinChooser {
      * left join's ER is different from inner join's
      * ex:t1,t2 ,if t1 left join t2 on
      * t1.id=t2.id can be pushed
-     * < we cna't change left join's structure>
+     * < we can't change left join's structure>
      *
      * @return
      */
@@ -107,6 +107,7 @@ public class ERJoinChooser {
             return null;
         else if (!PlanUtil.isERNode(child) && child.type() != PlanNode.PlanNodeType.TABLE)
             return null;
+
         if (onItem == null || !onItem.type().equals(Item.ItemType.FIELD_ITEM))
             return null;
         Pair<TableNode, ItemField> joinColumnInfo = PlanUtil.findColumnInTableLeaf((ItemField) onItem, joinNode);
@@ -130,7 +131,7 @@ public class ERJoinChooser {
     /* ------------------- left join optimizer end -------------------- */
 
     /**
-     * inner join's ER, rebuild inner joi's unit
+     * inner join's ER, rebuild inner join's unit
      *
      * @return
      */
@@ -390,7 +391,8 @@ public class ERJoinChooser {
     private boolean isUnit(PlanNode node) {
         if (isGlobalTree(node))
             return true;
-        else return node.type() != PlanNode.PlanNodeType.JOIN || node.isWithSubQuery() || !((JoinNode) node).isInnerJoin();
+        else
+            return node.type() != PlanNode.PlanNodeType.JOIN || node.isWithSubQuery() || !((JoinNode) node).isInnerJoin();
     }
 
     /**
diff --git a/src/main/java/com/actiontech/dble/plan/optimizer/GlobalTableProcessor.java b/src/main/java/com/actiontech/dble/plan/optimizer/GlobalTableProcessor.java
index 9def8ceb7..a09cb780d 100644
--- a/src/main/java/com/actiontech/dble/plan/optimizer/GlobalTableProcessor.java
+++ b/src/main/java/com/actiontech/dble/plan/optimizer/GlobalTableProcessor.java
@@ -55,8 +55,7 @@ public final class GlobalTableProcessor {
         if (PlanUtil.isERNode(tn)) {
             // treat er join as an un global table
             tn.setUnGlobalTableCount(1);
-            Set<String> newSet = new HashSet<>();
-            newSet.addAll(tn.getReferedTableNodes().get(0).getNoshardNode());
+            Set<String> newSet = new HashSet<>(tn.getReferedTableNodes().get(0).getNoshardNode());
             tn.setNoshardNode(newSet);
         } else {
             int unGlobalCount = calcUnGlobalCount(tn);
@@ -84,7 +83,9 @@ public final class GlobalTableProcessor {
                     if (left.getUnGlobalTableCount() == 0) { // left node is global,left join will not push down
                         tn.setNoshardNode(null);
                         status = false;
-                    } else if (left.type() == PlanNode.PlanNodeType.TABLE || PlanUtil.isERNode(left)) {
+                    } else if (left.type() == PlanNode.PlanNodeType.TABLE ||
+                            PlanUtil.isERNode(left) ||
+                            left.getNoshardNode() != null && left.getNoshardNode().size() > 0) {
                         if (!isGlobalTableBigEnough(jn)) {
                             tn.setNoshardNode(null);
                             status = false;