Alter doesn't show in processlist I'm performing an alter. It's currently running on a large table (300,000,000).

MariaDB [my_database]&gt; ALTER TABLE my_table
    -&gt; add INDEX a (x, y, z),
    -&gt; add INDEX d (x);
Stage: 1 of 2 'copy to tmp table'   60.1% of stage done


But the processlist doesn't mention it, with repeated queries. 

MariaDB [my_database]&gt; show full processlist;
+----+------+-----------------+-------------+---------+------+-------+-----------------------+----------+
| Id | User | Host            | db          | Command | Time | State | Info                  | Progress |
+----+------+-----------------+-------------+---------+------+-------+-----------------------+----------+
|  6 | apps | localhost:52235 | my_database | Sleep   |  304 |       | NULL                  |    0.000 |
| 33 | apps | localhost       | my_database | Query   |    0 | NULL  | show full processlist |    0.000 |
+----+------+-----------------+-------------+---------+------+-------+-----------------------+----------+
2 rows in set (0.01 sec)


I would expect it to show up. Any ideas why not?
It sounds like the user that's executing the ALTER TABLE and the user who's running SHOW PROCESSLIST are not the same user, and the second user lacks the PROCESS privilege.

If you have the PROCESS privilege, you can see all threads. Otherwise, you can see only your own threads (that is, threads associated with the MySQL account that you are using).
— http://dev.mysql.com/doc/refman/5.6/en/show-processlist.html