[SPARK-8972] [SQL] Incorrect result for rollup

We don't support the complex expression keys in the rollup/cube, and we even will not report it if we have the complex group by keys, that will cause very confusing/incorrect result.

e.g. `SELECT key%100 FROM src GROUP BY key %100 with ROLLUP`

This PR adds an additional project during the analyzing for the complex GROUP BY keys, and that projection will be the child of `Expand`, so to `Expand`, the GROUP BY KEY are always the simple key(attribute names).

Author: Cheng Hao <hao.cheng@intel.com>

Closes #7343 from chenghao-intel/expand and squashes the following commits:

1ebbb59 [Cheng Hao] update the comment
827873f [Cheng Hao] update as feedback
34def69 [Cheng Hao] Add more unit test and comments
c695760 [Cheng Hao] fix bug of incorrect result for rollup

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala

@@ -194,16 +194,52 @@ class Analyzer(
     }
 
     def apply(plan: LogicalPlan): LogicalPlan = plan transform {
+      case a if !a.childrenResolved => a // be sure all of the children are resolved.
       case a: Cube =>
         GroupingSets(bitmasks(a), a.groupByExprs, a.child, a.aggregations)
       case a: Rollup =>
         GroupingSets(bitmasks(a), a.groupByExprs, a.child, a.aggregations)
       case x: GroupingSets =>
         val gid = AttributeReference(VirtualColumn.groupingIdName, IntegerType, false)()
+        // We will insert another Projection if the GROUP BY keys contains the
+        // non-attribute expressions. And the top operators can references those
+        // expressions by its alias.
+        // e.g. SELECT key%5 as c1 FROM src GROUP BY key%5 ==>
+        //      SELECT a as c1 FROM (SELECT key%5 AS a FROM src) GROUP BY a
+
+        // find all of the non-attribute expressions in the GROUP BY keys
+        val nonAttributeGroupByExpressions = new ArrayBuffer[Alias]()
+
+        // The pair of (the original GROUP BY key, associated attribute)
+        val groupByExprPairs = x.groupByExprs.map(_ match {
+          case e: NamedExpression => (e, e.toAttribute)
+          case other => {
+            val alias = Alias(other, other.toString)()
+            nonAttributeGroupByExpressions += alias // add the non-attributes expression alias
+            (other, alias.toAttribute)
+          }
+        })
+
+        // substitute the non-attribute expressions for aggregations.
+        val aggregation = x.aggregations.map(expr => expr.transformDown {
+          case e => groupByExprPairs.find(_._1.semanticEquals(e)).map(_._2).getOrElse(e)
+        }.asInstanceOf[NamedExpression])
+
+        // substitute the group by expressions.
+        val newGroupByExprs = groupByExprPairs.map(_._2)
+
+        val child = if (nonAttributeGroupByExpressions.length > 0) {
+          // insert additional projection if contains the
+          // non-attribute expressions in the GROUP BY keys
+          Project(x.child.output ++ nonAttributeGroupByExpressions, x.child)
+        } else {
+          x.child
+        }
+
         Aggregate(
-          x.groupByExprs :+ VirtualColumn.groupingIdAttribute,
-          x.aggregations,
-          Expand(x.bitmasks, x.groupByExprs, gid, x.child))
+          newGroupByExprs :+ VirtualColumn.groupingIdAttribute,
+          aggregation,
+          Expand(x.bitmasks, newGroupByExprs, gid, child))
     }
   }
 

sql/hive/src/test/resources/golden/SPARK-8976 Wrong Result for CUBE #1-0-63b61fb3f0e74226001ad279be440864

@@ -0,0 +1,6 @@
+500	NULL	0
+91	0	1
+84	1	1
+105	2	1
+113	3	1
+107	4	1

sql/hive/src/test/resources/golden/SPARK-8976 Wrong Result for CUBE #2-0-7a511f02a16f0af4f810b1666cfcd896

@@ -0,0 +1,10 @@
+1	NULL	-3	2
+1	NULL	-1	2
+1	NULL	3	2
+1	NULL	4	2
+1	NULL	5	2
+1	NULL	6	2
+1	NULL	12	2
+1	NULL	14	2
+1	NULL	15	2
+1	NULL	22	2

sql/hive/src/test/resources/golden/SPARK-8976 Wrong Result for GroupingSet-0-8c14c24670a4b06c440346277ce9cf1c

@@ -0,0 +1,10 @@
+1	NULL	-3	2
+1	NULL	-1	2
+1	NULL	3	2
+1	NULL	4	2
+1	NULL	5	2
+1	NULL	6	2
+1	NULL	12	2
+1	NULL	14	2
+1	NULL	15	2
+1	NULL	22	2

sql/hive/src/test/resources/golden/SPARK-8976 Wrong Result for Rollup #1-0-a78e3dbf242f240249e36b3d3fd0926a

@@ -0,0 +1,6 @@
+500	NULL	0
+91	0	1
+84	1	1
+105	2	1
+113	3	1
+107	4	1

sql/hive/src/test/resources/golden/SPARK-8976 Wrong Result for Rollup #2-0-bf180c9d1a18f61b9d9f31bb0115cf89

@@ -0,0 +1,10 @@
+1	0	5	3
+1	0	15	3
+1	0	25	3
+1	0	60	3
+1	0	75	3
+1	0	80	3
+1	0	100	3
+1	0	140	3
+1	0	145	3
+1	0	150	3

sql/hive/src/test/resources/golden/SPARK-8976 Wrong Result for Rollup #3-0-9257085d123728730be96b6d9fbb84ce

@@ -0,0 +1,10 @@
+1	0	5	3
+1	0	15	3
+1	0	25	3
+1	0	60	3
+1	0	75	3
+1	0	80	3
+1	0	100	3
+1	0	140	3
+1	0	145	3
+1	0	150	3

sql/hive/src/test/scala/org/apache/spark/sql/hive/execution/HiveQuerySuite.scala

@@ -85,6 +85,60 @@ class HiveQuerySuite extends HiveComparisonTest with BeforeAndAfter {
     }
   }
 
+  createQueryTest("SPARK-8976 Wrong Result for Rollup #1",
+    """
+      SELECT count(*) AS cnt, key % 5,GROUPING__ID FROM src group by key%5 WITH ROLLUP
+    """.stripMargin)
+
+  createQueryTest("SPARK-8976 Wrong Result for Rollup #2",
+    """
+      SELECT
+        count(*) AS cnt,
+        key % 5 as k1,
+        key-5 as k2,
+        GROUPING__ID as k3
+      FROM src group by key%5, key-5
+      WITH ROLLUP ORDER BY cnt, k1, k2, k3 LIMIT 10
+    """.stripMargin)
+
+  createQueryTest("SPARK-8976 Wrong Result for Rollup #3",
+    """
+      SELECT
+        count(*) AS cnt,
+        key % 5 as k1,
+        key-5 as k2,
+        GROUPING__ID as k3
+      FROM (SELECT key, key%2, key - 5 FROM src) t group by key%5, key-5
+      WITH ROLLUP ORDER BY cnt, k1, k2, k3 LIMIT 10
+    """.stripMargin)
+
+  createQueryTest("SPARK-8976 Wrong Result for CUBE #1",
+    """
+      SELECT count(*) AS cnt, key % 5,GROUPING__ID FROM src group by key%5 WITH CUBE
+    """.stripMargin)
+
+  createQueryTest("SPARK-8976 Wrong Result for CUBE #2",
+    """
+      SELECT
+        count(*) AS cnt,
+        key % 5 as k1,
+        key-5 as k2,
+        GROUPING__ID as k3
+      FROM (SELECT key, key%2, key - 5 FROM src) t group by key%5, key-5
+      WITH CUBE ORDER BY cnt, k1, k2, k3 LIMIT 10
+    """.stripMargin)
+
+  createQueryTest("SPARK-8976 Wrong Result for GroupingSet",
+    """
+      SELECT
+        count(*) AS cnt,
+        key % 5 as k1,
+        key-5 as k2,
+        GROUPING__ID as k3
+      FROM (SELECT key, key%2, key - 5 FROM src) t group by key%5, key-5
+      GROUPING SETS (key%5, key-5) ORDER BY cnt, k1, k2, k3 LIMIT 10
+    """.stripMargin)
+
   createQueryTest("insert table with generator with column name",
     """
       |  CREATE TABLE gen_tmp (key Int);