maria-discuss team mailing list archive

[Sergei Golubchik <serg@xxxxxxxxxxx>]

Hi, Federico!

On Mar 27, Federico Razzoli wrote:
> Hi Sergei
> 
> You can repeat this very easily:
> 
> MariaDB [test]> CREATE TABLE t_connect (c INT PRIMARY KEY) ENGINE=CONNECT TABLE_TYPE=CSV;
> Query OK, 0 rows affected, 1 warning (0.11 sec)
> 
> Warning (Code 1105): No file name. Table will use t_connect.csv
> MariaDB [test]> INSERT INTO t_connect VALUES (1),(2);Query OK, 2 rows affected (0.00 sec)
> Records: 2  Duplicates: 0  Warnings: 0
> 
> MariaDB [test]> EXPLAIN SELECT MAX(c) FROM t_connect;
> +------+-------------+-----------+------+---------------+------+---------+------+------+-------+
> | id   | select_type | table     | type | possible_keys | key  | key_len | ref  | rows | Extra |
> +------+-------------+-----------+------+---------------+------+---------+------+------+-------+
> |    1 | SIMPLE      | t_connect | ALL  | NULL          | NULL | NULL    | NULL |    4 |       |
> +------+-------------+-----------+------+---------------+------+---------+------+------+-------+
> 1 row in set (0.00 sec)
> 
> But adding more rows, the difference between the rows value and the reality becomes big.

Thanks, I've reported it as

https://mariadb.atlassian.net/browse/MDEV-6232

I tried to repeat it earlier, but then it uncovered other bugs in the
CONNECT indexes, they're fixed now. Your original query gets "Table was
optimized away", so I have to modified it a bit for the bug report.

Regards,
Sergei