From d25e615f8809b397d15372b453c2e0f6bcc2959a Mon Sep 17 00:00:00 2001
From: wenfang <wenfang@360.cn>
Date: Tue, 12 Nov 2019 14:27:03 +0800
Subject: [PATCH] [CORE]Fix the bug that don't pushdown mysql datasource when
 there are some spark-provided functions in subquery #64

This PR solved the first question about Issues[61]https://github.com/Qihoo360/XSQL/issues/61, don't `pushdown `MySQL `datasource `when there are some functions  provided by spark in subquery.
---
 .../mysql/MysqlSpecialStrategy.scala          | 32 +++++++++++--------
 1 file changed, 18 insertions(+), 14 deletions(-)

diff --git a/sql/xsql/src/main/scala/org/apache/spark/sql/xsql/execution/datasources/mysql/MysqlSpecialStrategy.scala b/sql/xsql/src/main/scala/org/apache/spark/sql/xsql/execution/datasources/mysql/MysqlSpecialStrategy.scala
index 23be7de..fbfc6ff 100644
--- a/sql/xsql/src/main/scala/org/apache/spark/sql/xsql/execution/datasources/mysql/MysqlSpecialStrategy.scala
+++ b/sql/xsql/src/main/scala/org/apache/spark/sql/xsql/execution/datasources/mysql/MysqlSpecialStrategy.scala
@@ -474,25 +474,29 @@ class TransmitOriginalQuery(session: SparkSession) extends Rule[LogicalPlan] {
       "rand",
       "cast",
       "like")
-    plan.expressions.forall {
-      case a: Alias =>
-        if (a.child.isInstanceOf[AttributeReference] || a.child.isInstanceOf[ScalarSubquery]
+
+    @inline def functionNotPushdown(plan: LogicalPlan): Boolean = {
+      plan.expressions.exists {
+        case a: Alias =>
+          if (a.child.isInstanceOf[AttributeReference] || a.child.isInstanceOf[ScalarSubquery]
             || a.child.isInstanceOf[BinaryArithmetic]) {
-          true
-        } else {
-          val func = if (a.child.isInstanceOf[AggregateExpression]) {
-            a.child.asInstanceOf[AggregateExpression].aggregateFunction
-          } else {
-            a.child
-          }
-          if (!pushdownFunctions.contains(func.prettyName)) {
             false
           } else {
-            true
+            val func = if (a.child.isInstanceOf[AggregateExpression]) {
+              a.child.asInstanceOf[AggregateExpression].aggregateFunction
+            } else {
+              a.child
+            }
+            if (pushdownFunctions.contains(func.prettyName)) {
+              false
+            } else {
+              true
+            }
           }
-        }
-      case _ => true
+        case _ => false
+      }
     }
+    plan.find(functionNotPushdown).isEmpty
   }
 
   /**