manual merge

sql/field.cc:
  Auto merged
sql/item.cc:
  Auto merged
sql/item_cmpfunc.cc:
  Auto merged
sql/item_cmpfunc.h:
  Auto merged
sql/item_func.cc:
  Auto merged
sql/mysqld.cc:
  Auto merged
sql/opt_range.cc:
  Auto merged
sql/sql_parse.cc:
  Auto merged
sql/sql_select.cc:
  Auto merged
sql/sql_view.cc:
  Auto merged
strings/ctype-utf8.c:
  Auto merged

1 files changed, 21 insertions, 0 deletions

diff --git a/mysql-test/t/group_by.test b/mysql-test/t/group_by.test
index 6845f310843..2defb480deb 100644
--- a/mysql-test/t/group_by.test
+++ b/mysql-test/t/group_by.test
@@ -543,6 +543,27 @@ SELECT hostname, COUNT(DISTINCT user_id) as no FROM t1
 DROP TABLE t1;
 
 #
+# Bug#11211: Ambiguous column reference in GROUP BY.
+#
+
+create table t1 (c1 char(3), c2 char(3));
+create table t2 (c3 char(3), c4 char(3));
+insert into t1 values ('aaa', 'bb1'), ('aaa', 'bb2');
+insert into t2 values ('aaa', 'bb1'), ('aaa', 'bb2');
+
+# query with ambiguous column reference 'c2'
+--disable_ps_protocol
+select t1.c1 as c2 from t1, t2 where t1.c2 = t2.c4
+group by c2;
+show warnings;
+--enable_ps_protocol
+
+# this query has no ambiguity
+select t1.c1 as c2 from t1, t2 where t1.c2 = t2.c4
+group by t1.c1;
+
+show warnings;
+drop table t1, t2;
 
 #
 # Test for bug #11414: crash on Windows for a simple GROUP BY query