Comment 1 for bug 798597

I succeeded to reproduce this bug with the latest 5.1 build using the test case from
the bug #798576:

Server version: 5.1.58-MariaDB-debug Source distribution

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MariaDB [test]> CREATE TABLE t1 ( f1 int NOT NULL , f2 int NOT NULL ) ;
Query OK, 0 rows affected (0.02 sec)

MariaDB [test]> INSERT INTO t1 VALUES (214,0),(6,6);
Query OK, 2 rows affected (0.01 sec)
Records: 2 Duplicates: 0 Warnings: 0

MariaDB [test]>
MariaDB [test]> CREATE TABLE t2 ( f2 int) ;
Query OK, 0 rows affected (0.00 sec)

MariaDB [test]> INSERT INTO t2 VALUES (88),(88);
Query OK, 2 rows affected (0.00 sec)
Records: 2 Duplicates: 0 Warnings: 0

MariaDB [test]>
MariaDB [test]> CREATE ALGORITHM=MERGE VIEW v2 AS SELECT t1.f1, t2.f2 FROM (t2 LEFT JOIN t1 ON (t2.f2 <> t1.f1)) WHERE (t1.f2 <= 'up') ;
Query OK, 0 rows affected (0.00 sec)

MariaDB [test]> SELECT f1 , MIN(f2) FROM v2 GROUP BY f1;
ERROR 1062 (23000): Duplicate entry '214' for key 'group_key'

The bug is not reproducible with the latest mysql-5.1.
It should be fixed in maria-5.1.