删除数据库失败，提示：there is 1 other session using the database

解决办法：

SELECT pg_terminate_backend(pg_stat_activity.pid)
FROM pg_stat_activity WHERE datname='test_database'
AND pid<>pg_backend_pid();

使用上述命令先关闭活跃的连接用户

此时再执行：DROP DATABASE test_database;