postgres=# drop database k8s_kong;
ERROR: database "k8s_kong" is being accessed by other users
DETAIL: There are 24 other sessions using the database.
说明该k8s_kong库正在被人连接。解决方法是：
查询出连接该数据库的进程，并将其杀死(比较暴力)
postgres=# select pg_terminate_backend(pid) from pg_stat_activity where DATNAME = 'k8s_kong';
ERROR: must be a member of the role whose process is being terminated or member of pg_signal_backend
postgres=# grant pg_signal_backend to pointsmart_ops; 给用户授权pg_signal_backend角色，不然没权限执行不了下一步
Command OK
postgres=# select pg_terminate_backend(pid) from pg_stat_activity where DATNAME = 'k8s_kong';
+----------------------+
| pg_terminate_backend |
+----------------------+
| t |
| t |
| t |
| t |
| t |
| t |
| t |
| t |
| t |
| t |
| t |
| t |
| t |
| t |
| t |
| t |
| t |
| t |
| t |
| t |
| t |
| t |
| t |
| t |
+----------------------+
24 rows in set
postgres=# drop database k8s_kong;
Command OK
