Unable to get rid of orphan temporary tables

After migrating from MariaDB 5.5 to 10.0, I noticed an error message mentioning a table named piwik/#sql-1526_3a. From there I started googling and landed on the [innodb troubleshooting docs](https://dev.mysql.com/doc/refman/5.6/en/innodb-troubleshooting-datadict.html#innodb-orphan-temporary-tables) Indeed, SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_TABLES WHERE NAME LIKE '%#sql%'; gives the following result: MariaDB [(none)]> SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_TABLES WHERE NAME LIKE '%#sql%'; +----------+--------+----------------+------+--------+-------+ | TABLE_ID | SCHEMA | NAME | FLAG | N_COLS | SPACE | +----------+--------+----------------+------+--------+-------+ | 323 | piwik | #sql-1526_3a | 1 | 11 | 320 | | 265 | piwik | #sql-5305_92b0 | 1 | 24 | 262 | | 321 | piwik | #sql-7920_48 | 1 | 24 | 318 | +----------+--------+----------------+------+--------+-------+ I tried to follow MySQL troubleshooting instructions and did: MariaDB [(none)]> use piwik Database changed MariaDB [piwik]> drop table #mysql50##sql-1526_3a; ERROR 1051 (42S02): Unknown table '#mysql50##sql-1526_3a' From there, I read more blog posts and stack exchange answers and noticed that there are no #sql-1526_3a.idb and #sql-1526_3a.frm files in my /var/lib/mysql/piwik/ folder. I then tried the following: $ cd /var/lib/mysql/piwik $ cp piwik_user.ibd #sql-1526_3a.ibd $ cp piwik_user.frm #sql-1526_3a.frm and restarted MariaDB. Then I tried droping the table again: MariaDB [piwik]> drop table #mysql50##sql-1526_3a; Database changed Query OK, 0 rows affected (0.00sec) Horray?!! Well, SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_TABLES WHERE NAME LIKE '%#sql%'; still lists the #sql-1526_3a table. On disk, the .frm file got deleted but the .ibd file remains. So? Does someone know how I can remove these orphan tables for real? --- **EDIT** It seems to me these trailing temporary tables are "referenced" from /var/lib/mysql/ibdata1 before I shrunk it and enabled innodb_file_per_table = 1.