From 1c9a0920c34fc4e64fa9ef91aec4cfeb02917b2f Mon Sep 17 00:00:00 2001
From: wangfei <wangfei1@huawei.com>
Date: Wed, 29 Apr 2015 17:17:57 +0800
Subject: [PATCH] added Substitution bastch

---
 .../sql/catalyst/analysis/Analyzer.scala      | 71 +++++++++++++------
 1 file changed, 48 insertions(+), 23 deletions(-)

diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala
index 5e42b409dcc59..0fe5e2d1ade65 100644
--- a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala
@@ -47,12 +47,21 @@ class Analyzer(
 
   val fixedPoint = FixedPoint(maxIterations)
 
+  /**
+   * Override to provide additional rules for the "Substitution" batch.
+   */
+  val extendedSubstitutionRules: Seq[Rule[LogicalPlan]] = Nil
+  
   /**
    * Override to provide additional rules for the "Resolution" batch.
    */
   val extendedResolutionRules: Seq[Rule[LogicalPlan]] = Nil
 
   lazy val batches: Seq[Batch] = Seq(
+    Batch("Substitution", fixedPoint,
+      CTESubstitution ::
+      Nil ++
+      extendedSubstitutionRules : _*),
     Batch("Resolution", fixedPoint,
       ResolveRelations ::
       ResolveReferences ::
@@ -68,6 +77,38 @@ class Analyzer(
       extendedResolutionRules : _*)
   )
 
+  /**
+   * Substitute CTE definitions
+   */
+  object CTESubstitution extends Rule[LogicalPlan] {
+    def apply(plan: LogicalPlan): LogicalPlan = {
+      val (realPlan, cteRelations) = plan match {
+        case With(child, relations) =>
+          (child, relations)
+        case other => (other, Map.empty[String, LogicalPlan])
+      }
+      substituteCTE(realPlan, cteRelations)
+    }
+
+    def substituteCTE(plan: LogicalPlan, cteRelations: Map[String, LogicalPlan]): LogicalPlan = {
+      plan transform {
+        case i @ InsertIntoTable(u: UnresolvedRelation, _, _, _, _) =>
+          // In hive, if there is same table name in database and CTE definition,
+          // hive will use the table in database, not the CTE one.
+          // Taking into account the reasonableness and the implementation complexity,
+          // here use the CTE definition first, check table name only and ignore database name
+          val relation = cteRelations.get(u.tableIdentifier.last)
+            .map(relation => u.alias.map(Subquery(_, relation)).getOrElse(relation))
+            .getOrElse(u)
+          i.copy(table = relation)
+        case u : UnresolvedRelation =>
+          cteRelations.get(u.tableIdentifier.last)
+            .map(relation => u.alias.map(Subquery(_, relation)).getOrElse(relation))
+            .getOrElse(u)
+      }
+    }
+  }
+
   /**
    * Removes no-op Alias expressions from the plan.
    */
@@ -169,36 +210,20 @@ class Analyzer(
    * Replaces [[UnresolvedRelation]]s with concrete relations from the catalog.
    */
   object ResolveRelations extends Rule[LogicalPlan] {
-    def getTable(u: UnresolvedRelation, cteRelations: Map[String, LogicalPlan]): LogicalPlan = {
+    def getTable(u: UnresolvedRelation): LogicalPlan = {
       try {
-        // In hive, if there is same table name in database and CTE definition,
-        // hive will use the table in database, not the CTE one.
-        // Taking into account the reasonableness and the implementation complexity,
-        // here use the CTE definition first, check table name only and ignore database name
-        cteRelations.get(u.tableIdentifier.last)
-          .map(relation => u.alias.map(Subquery(_, relation)).getOrElse(relation))
-          .getOrElse(catalog.lookupRelation(u.tableIdentifier, u.alias))
+        catalog.lookupRelation(u.tableIdentifier, u.alias)
       } catch {
         case _: NoSuchTableException =>
           u.failAnalysis(s"no such table ${u.tableName}")
       }
     }
 
-    def apply(plan: LogicalPlan): LogicalPlan = {
-      val (realPlan, cteRelations) = plan match {
-        // TODO allow subquery to define CTE
-        // Add cte table to a temp relation map,drop `with` plan and keep its child
-        case With(child, relations) => (child, relations)
-        case other => (other, Map.empty[String, LogicalPlan])
-      }
-
-      realPlan transform {
-        case i@InsertIntoTable(u: UnresolvedRelation, _, _, _, _) =>
-          i.copy(
-            table = EliminateSubQueries(getTable(u, cteRelations)))
-        case u: UnresolvedRelation =>
-          getTable(u, cteRelations)
-      }
+    def apply(plan: LogicalPlan): LogicalPlan = plan transform {
+      case i@InsertIntoTable(u: UnresolvedRelation, _, _, _, _) =>
+        i.copy(table = EliminateSubQueries(getTable(u)))
+      case u: UnresolvedRelation =>
+        getTable(u, cteRelations)
     }
   }