Figured out the tables.. DB is nova_api and tables are aggregates and aggregate_metadata.. due to foreign key need to delete from aggregate_metadate before deleting from aggregates.

MariaDB [(none)]> use nova_api;
Reading table information for completion of table and column names
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Database changed

MariaDB [nova_api]> select * from aggregates;
+---------------------+---------------------+----+--------------------------------------+----------+
| created_at          | updated_at          | id | uuid                                 | name     |
+---------------------+---------------------+----+--------------------------------------+----------+
| 2017-08-22 01:46:32 | 2017-08-30 14:02:31 |  1 | e4a4a16e-7513-42fc-9808-32eab5ce6077 | compute  |
| 2017-08-30 17:41:34 | NULL                |  2 | 6caa9100-012a-40fa-81fd-3b9de6554789 | allnodes |
+---------------------+---------------------+----+--------------------------------------+----------+


MariaDB [nova_api]> delete from aggregate_hosts where aggregate_id=1

MariaDB [nova_api]> select * from aggregate_metadata;
+---------------------+------------+----+--------------+-------------------+----------+
| created_at          | updated_at | id | aggregate_id | key               | value    |
+---------------------+------------+----+--------------+-------------------+----------+
| 2017-08-22 01:47:14 | NULL       |  1 |            1 | availability_zone | nova2    |
| 2017-08-30 17:41:34 | NULL       |  2 |            2 | availability_zone | allnodes |
+---------------------+------------+----+--------------+-------------------+----------+
2 rows in set (0.00 sec)

MariaDB [nova_api]> delete from aggregate_metadata where id =1;

MariaDB [nova_api]> delete from aggregates where id =1;
Query OK, 1 row affected (0.02 sec)