定期清理长事务、长时间未结束的SQL 应定期检查并清理长事务、长时间未结束的SQL: 连接所有CN、DN主节点,执行以下SQL,查询超过1小时的会话: select pid,client_addr,state_change,query_start,state_change,EXTRACT(EPOCH FROM (now()-query_start)),query,state,usename,application_name from pg_stat_activity where EXTRACT(EPOCH FROM (now()-query_start