Am 16.09.19 um 16:43 schrieb Marko Mäkelä:
it's a shame that you simply can't get rid of garbage from the global tablespace
Starting with MDEV-14585 InnoDB actually does drop #sql- tables during startup. The #sql2 tables are intentionally preserved, because during ALTER TABLE…ALGORIHTM=COPY there are multiple internal commits, and if the server is killed at the right moment, then the user table will be known only by #sql- and #sql2 names. We do not want to remove the only copy of the table.
Ultimately, for new DDL statements, this should be fixed when MDEV-17567 implements Atomic DDL. I do not think that we can even then safely remove #sql2 tables from old installations, because we must think of upgrade scenarios.
that all don't justify why the drop table simply can't remove the reference to something that literally don#t exist for a whole decade either that idiotic table is known or it's unknown if it's unknow get rid of it or at least allow the admin to do so with doing some crazy dance introducing way more room for troubles than just forget about something which isn't there anyways MariaDB [(none)]> SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_TABLES WHERE NAME LIKE '%#sql%'; +----------+----------------------+------+--------+-------+------------+---------------+------------+ | TABLE_ID | NAME | FLAG | N_COLS | SPACE | ROW_FORMAT | ZIP_PAGE_SIZE | SPACE_TYPE | +----------+----------------------+------+--------+-------+------------+---------------+------------+ | 672 | dbmail/#sql2-704-271 | 41 | 5 | 545 | Compressed | 8192 | Single | +----------+----------------------+------+--------+-------+------------+---------------+------------+ 1 row in set (0.002 sec) MariaDB [(none)]> use dbmail ERROR 1051 (42S02): Unknown table 'dbmail.dbmail/#sql2-704-271' MariaDB [dbmail]> DROP TABLE `dbmail#sql2-704-271`; ERROR 1051 (42S02): Unknown table 'dbmail.dbmail#sql2-704-271' MariaDB [dbmail]>