From 6a2123cbe3312b83bca509b07fbdae35b941e8a4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E9=AB=98=E9=93=81?= <shaojin.wensj@alibaba-inc.com>
Date: Sun, 3 Oct 2021 02:13:10 +0800
Subject: [PATCH] fix #4486

---
 .../druid/sql/parser/SQLSelectParser.java     |  8 +++---
 src/test/resources/bvt/parser/odps-8.txt      | 28 ++++++++++++++++++-
 2 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/main/java/com/alibaba/druid/sql/parser/SQLSelectParser.java b/src/main/java/com/alibaba/druid/sql/parser/SQLSelectParser.java
index f5c9b18fc5..95ede9506c 100644
--- a/src/main/java/com/alibaba/druid/sql/parser/SQLSelectParser.java
+++ b/src/main/java/com/alibaba/druid/sql/parser/SQLSelectParser.java
@@ -1077,11 +1077,11 @@ public class SQLSelectParser extends SQLParser {
             		|| lexer.token == Token.SEL) {
                 SQLSelect select = select();
                 accept(Token.RPAREN);
-                if (select.getQuery() instanceof SQLSelectQueryBlock) {
-                    ((SQLSelectQueryBlock) select.getQuery()).setParenthesized(true);
-                }
+                SQLSelectQuery selectQuery = select.getQuery();
+                selectQuery.setParenthesized(true);
 
-                SQLSelectQuery query = queryRest(select.getQuery(), true);
+                boolean acceptUnion = !(selectQuery instanceof SQLUnionQuery);
+                SQLSelectQuery query = queryRest(selectQuery, acceptUnion);
                 if (query instanceof SQLUnionQuery) {
                     tableSource = new SQLUnionQueryTableSource((SQLUnionQuery) query);
                 } else {
diff --git a/src/test/resources/bvt/parser/odps-8.txt b/src/test/resources/bvt/parser/odps-8.txt
index d288734841..6f12f961d6 100644
--- a/src/test/resources/bvt/parser/odps-8.txt
+++ b/src/test/resources/bvt/parser/odps-8.txt
@@ -13,4 +13,30 @@ from (
         union
         select id, collectId, c2
         from (select id, collectId, c2 from table_2)
-)
\ No newline at end of file
+)
+---------------------------
+SELECT *
+FROM (
+	SELECT id, collectId, 3 AS c_0
+	FROM (
+		SELECT *
+		FROM tc_merchant
+		WHERE collectId IN (
+			SELECT collect_id
+			FROM cte_merchant
+		)
+		UNION
+		SELECT *
+		FROM st_merchant
+		WHERE collectId IN (
+			SELECT collect_id
+			FROM st_merchant_tmp
+		)
+	)
+	UNION
+	SELECT id, collectId, c2
+	FROM (
+		SELECT id, collectId, c2
+		FROM table_2
+	)
+)