Fixed bug #29392.

This bug may manifest itself for select queries over a multi-table view
that includes an ORDER BY clause in its definition. If the select list of 
the query contains references to the same view column with different
aliases the names of the columns in the result output will be nevertheless
the same, coinciding with one of the alias.

The bug happened because the method Item_ref::get_tmp_table_item that
was inherited by the class Item_direct_view_ref ignored the fact that
the name of the view column reference must be inherited by the fields
of the temporary table that was created in order to get the result rows
sorted.


mysql-test/r/view.result:
  Added a test case for bug #29392.
mysql-test/t/view.test:
  Added a test case for bug #29392.
sql/item.h:
  Fixed bug #29392.
  This bug may manifest itself for select queries over a multi-table view
  that includes an ORDER BY clause in its definition. If the select list of 
  the query contains references to the same view column with different
  aliases the names of the columns in the result output will be nevertheless
  the same, coinciding with one of the alias.
  
  The bug happened because the method Item_ref::get_tmp_table_item that
  was inherited by the class Item_direct_view_ref ignored the fact that
  the name of the view column reference must be inherited by the fields
  of the temporary table that was created in order to get the result rows
  sorted.
  
  Fixed by providing a proper implementation of the get_tmp_table_item 
  method for the Item_direct_view_ref class.

1 files changed, 55 insertions, 0 deletions

diff --git a/mysql-test/t/view.test b/mysql-test/t/view.test
index f670ac8a49d..c7f722a18a5 100644
--- a/mysql-test/t/view.test
+++ b/mysql-test/t/view.test
@@ -3348,4 +3348,59 @@ EXPLAIN SELECT a, SUM(b) FROM v1 WHERE a=1 GROUP BY a;
 DROP VIEW v1;
 DROP TABLE t1;
 
+#
+# Bug #29392: SELECT over a multi-table view with ORDER BY  
+#             selecting the same view column with two different aliases  
+#
+
+CREATE TABLE t1 (
+  person_id int NOT NULL PRIMARY KEY,
+  username varchar(40) default NULL,
+  status_flg char(1) NOT NULL default 'A'
+);
+
+CREATE TABLE t2 (
+  person_role_id int NOT NULL auto_increment PRIMARY KEY,
+  role_id int NOT NULL,
+  person_id int NOT NULL,
+  INDEX idx_person_id (person_id),
+  INDEX idx_role_id (role_id)
+);
+
+CREATE TABLE t3 (
+  role_id int NOT NULL auto_increment PRIMARY KEY,
+  role_name varchar(100) default NULL,
+  app_name varchar(40) NOT NULL,
+  INDEX idx_app_name(app_name)
+);
+
+CREATE VIEW v1 AS 
+SELECT profile.person_id AS person_id
+  FROM t1 profile, t2 userrole, t3 role
+    WHERE userrole.person_id = profile.person_id AND
+          role.role_id = userrole.role_id AND
+          profile.status_flg = 'A'
+  ORDER BY profile.person_id,role.app_name,role.role_name;
+
+INSERT INTO  t1 VALUES
+ (6,'Sw','A'), (-1136332546,'ols','e'), (0,'    *\n','0'),
+ (-717462680,'ENTS Ta','0'), (-904346964,'ndard SQL\n','0');
+
+INSERT INTO t2 VALUES
+  (1,3,6),(2,4,7),(3,5,8),(4,6,9),(5,1,6),(6,1,7),(7,1,8),(8,1,9),(9,1,10);
+
+INSERT INTO t3 VALUES 
+  (1,'NUCANS_APP_USER','NUCANSAPP'),(2,'NUCANS_TRGAPP_USER','NUCANSAPP'),
+  (3,'IA_INTAKE_COORDINATOR','IACANS'),(4,'IA_SCREENER','IACANS'),
+  (5,'IA_SUPERVISOR','IACANS'),(6,'IA_READONLY','IACANS'),
+  (7,'SOC_USER','SOCCANS'),(8,'CAYIT_USER','CAYITCANS'),
+  (9,'RTOS_DCFSPOS_SUPERVISOR','RTOS');
+ 
+EXPLAIN SELECT t.person_id AS a, t.person_id AS b FROM v1 t WHERE t.person_id=6;
+SELECT t.person_id AS a, t.person_id AS b FROM v1 t WHERE t.person_id=6;
+
+DROP VIEW v1;
+DROP TABLE t1,t2,t3;
+
 --echo End of 5.0 tests.
+