Revert "[SPARK-13321][SQL] Support nested UNION in parser"

This reverts commit 55d6fdf22d1d6379180ac09f364c38982897d9ff.

2 files changed, 0 insertions, 84 deletions

diff --git a/sql/catalyst/src/main/antlr3/org/apache/spark/sql/catalyst/parser/SparkSqlParser.g b/sql/catalyst/src/main/antlr3/org/apache/spark/sql/catalyst/parser/SparkSqlParser.g
index 3010d3ae0d..1db3aed658 100644
--- a/sql/catalyst/src/main/antlr3/org/apache/spark/sql/catalyst/parser/SparkSqlParser.g
+++ b/sql/catalyst/src/main/antlr3/org/apache/spark/sql/catalyst/parser/SparkSqlParser.g
@@ -2320,26 +2320,6 @@ regularBody[boolean topLevel]
    )
    |
    selectStatement[topLevel]
-   |
-   (LPAREN selectStatement0[true]) => nestedSetOpSelectStatement[topLevel]
-   ;
-
-nestedSetOpSelectStatement[boolean topLevel]
-   :
-   (
-   LPAREN s=selectStatement0[topLevel] RPAREN -> {$s.tree}
-   )
-   (set=setOpSelectStatement[$nestedSetOpSelectStatement.tree, topLevel])
-   -> {set == null}?
-      {$nestedSetOpSelectStatement.tree}
-   -> {$set.tree}
-   ;
-
-selectStatement0[boolean topLevel]
-   :
-   (selectStatement[true]) => selectStatement[topLevel]
-   |
-   (nestedSetOpSelectStatement[true]) => nestedSetOpSelectStatement[topLevel]
    ;
 
 selectStatement[boolean topLevel]
diff --git a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/CatalystQlSuite.scala b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/CatalystQlSuite.scala
index 812aa5acd8..53a8d6e53e 100644
--- a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/CatalystQlSuite.scala
+++ b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/CatalystQlSuite.scala
@@ -202,70 +202,6 @@ class CatalystQlSuite extends PlanTest {
       "from windowData")
   }
 
-  test("nesting UNION") {
-    val parsed = parser.parsePlan(
-      """
-       |SELECT  `u_1`.`id` FROM (((SELECT  `t0`.`id` FROM `default`.`t0`)
-       |UNION ALL (SELECT  `t0`.`id` FROM `default`.`t0`)) UNION ALL
-       |(SELECT  `t0`.`id` FROM `default`.`t0`)) AS u_1
-      """.stripMargin)
-
-    val expected = Project(
-      UnresolvedAlias(UnresolvedAttribute("u_1.id"), None) :: Nil,
-      SubqueryAlias("u_1",
-        Union(
-          Union(
-            Project(
-              UnresolvedAlias(UnresolvedAttribute("t0.id"), None) :: Nil,
-              UnresolvedRelation(TableIdentifier("t0", Some("default")), None)),
-            Project(
-              UnresolvedAlias(UnresolvedAttribute("t0.id"), None) :: Nil,
-              UnresolvedRelation(TableIdentifier("t0", Some("default")), None))),
-          Project(
-            UnresolvedAlias(UnresolvedAttribute("t0.id"), None) :: Nil,
-            UnresolvedRelation(TableIdentifier("t0", Some("default")), None)))))
-
-    comparePlans(parsed, expected)
-
-    val parsedSame = parser.parsePlan(
-      """
-       |SELECT  `u_1`.`id` FROM ((SELECT  `t0`.`id` FROM `default`.`t0`)
-       |UNION ALL (SELECT  `t0`.`id` FROM `default`.`t0`) UNION ALL
-       |(SELECT  `t0`.`id` FROM `default`.`t0`)) AS u_1
-      """.stripMargin)
-
-    comparePlans(parsedSame, expected)
-
-    val parsed2 = parser.parsePlan(
-      """
-       |SELECT  `u_1`.`id` FROM ((((SELECT  `t0`.`id` FROM `default`.`t0`)
-       |UNION ALL (SELECT  `t0`.`id` FROM `default`.`t0`)) UNION ALL
-       |(SELECT  `t0`.`id` FROM `default`.`t0`))
-       |UNION ALL (SELECT  `t0`.`id` FROM `default`.`t0`)) AS u_1
-      """.stripMargin)
-
-    val expected2 = Project(
-      UnresolvedAlias(UnresolvedAttribute("u_1.id"), None) :: Nil,
-      SubqueryAlias("u_1",
-        Union(
-          Union(
-            Union(
-              Project(
-                UnresolvedAlias(UnresolvedAttribute("t0.id"), None) :: Nil,
-                UnresolvedRelation(TableIdentifier("t0", Some("default")), None)),
-              Project(
-                UnresolvedAlias(UnresolvedAttribute("t0.id"), None) :: Nil,
-                UnresolvedRelation(TableIdentifier("t0", Some("default")), None))),
-            Project(
-              UnresolvedAlias(UnresolvedAttribute("t0.id"), None) :: Nil,
-              UnresolvedRelation(TableIdentifier("t0", Some("default")), None))),
-          Project(
-            UnresolvedAlias(UnresolvedAttribute("t0.id"), None) :: Nil,
-            UnresolvedRelation(TableIdentifier("t0", Some("default")), None)))))
-
-    comparePlans(parsed2, expected2)
-  }
-
   test("subquery") {
     parser.parsePlan("select (select max(b) from s) ss from t")
     parser.parsePlan("select * from t where a = (select b from s)")