[#MDEV-16427] dual table is implemented a bit flaky

SELECT * FROM dual;

ERROR 1096 (HY000): No tables used

The DUAL table has one column, DUMMY, defined to be VARCHAR2(1), and contains one row with a value X
https://docs.oracle.com/cd/B19306_01/server.102/b14200/queries009.htm

select * from test join dual;

ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'dual' at line 1

select * from dual join test;

ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'join test' at line 1

So the "correct" results in oracle terms should be:

select * from `DUAL`;

+-------+

| DUMMY |

+-------+

| X     |

+-------+

select * from test join `DUAL`;

+----+--------------+---------------------+-------+

| id | data         | ts                  | DUMMY |

+----+--------------+---------------------+-------+

|  1 | Some bla bla | 2018-06-07 22:03:52 | X     |

+----+--------------+---------------------+-------+

select * from `DUAL` join test;

+-------+----+--------------+---------------------+

| DUMMY | id | data         | ts                  |

+-------+----+--------------+---------------------+

| X     |  1 | Some bla bla | 2018-06-07 22:03:52 |

+-------+----+--------------+---------------------+

This could matter because the dual table is fundamental in Oracle world and many internal and external queries may rely on exactly this behaviour...

[MDEV-16427] dual table is implemented a bit flaky Created: 2018-06-07 Updated: 2018-06-21
Status:	Open
Project:	MariaDB Server
Component/s:	Server
Fix Version/s:	None

[MDEV-16427] dual table is implemented a bit flaky Created: 2018-06-07 Updated: 2018-06-21