[SPARK-9371][SQL] fix the support for special chars in column names for hive context

Author: Wenchen Fan <[email protected]>

Closes #7684 from cloud-fan/hive and squashes the following commits:

da21ffe [Wenchen Fan] fix the support for special chars in column names for hive context

Author: cloud-fan

sql/hive/src/main/scala/org/apache/spark/sql/hive/HiveQl.scala

@@ -1321,11 +1321,11 @@ https://cwiki.apache.org/confluence/display/Hive/Enhanced+Aggregation%2C+Cube%2C
     /* Attribute References */
     case Token("TOK_TABLE_OR_COL",
            Token(name, Nil) :: Nil) =>
-      UnresolvedAttribute(cleanIdentifier(name))
+      UnresolvedAttribute.quoted(cleanIdentifier(name))
     case Token(".", qualifier :: Token(attr, Nil) :: Nil) =>
       nodeToExpr(qualifier) match {
-        case UnresolvedAttribute(qualifierName) =>
-          UnresolvedAttribute(qualifierName :+ cleanIdentifier(attr))
+        case UnresolvedAttribute(nameParts) =>
+          UnresolvedAttribute(nameParts :+ cleanIdentifier(attr))
         case other => UnresolvedExtractValue(other, Literal(attr))
       }
 

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

@@ -1067,4 +1067,12 @@ class SQLQuerySuite extends QueryTest with SQLTestUtils {
     )
     TestHive.dropTempTable("test_SPARK8588")
   }
+
+  test("SPARK-9371: fix the support for special chars in column names for hive context") {
+    TestHive.read.json(TestHive.sparkContext.makeRDD(
+      """{"a": {"c.b": 1}, "b.$q": [{"a@!.q": 1}], "q.w": {"w.i&": [1]}}""" :: Nil))
+      .registerTempTable("t")
+
+    checkAnswer(sql("SELECT a.`c.b`, `b.$q`[0].`a@!.q`, `q.w`.`w.i&`[0] FROM t"), Row(1, 1, 1))
+  }
 }