PolarDB锁事务连接被意外断开 是可能啥？

PolarDB锁事务连接被意外断开 是可能啥？### Error querying database. Cause: java.sql.SQLException: connection disabled

The error may exist in org/mvwchina/bussines/examination/examinationpaper/mapper/QuestionMapper.java (best guess)

The error may involve org.mvwchina.bussines.examination.examinationpaper.mapper.QuestionMapper.selectList

The error occurred while executing a query

SQL: SELECT id,sequence,bank_id,questionnaire_id,user_seq,answer_seq,orders,title,title_type,question_type,subquestion_count,optionz,answer,answer_keys,select_type,analysis,score,random_question,random_subquestion,random_option,random_answer,required,time_limit,tissue_id,tissue_name,creator,create_time,updator,update_time,parent_id,remark FROM exa_question WHERE (questionnaire_id IN (?))

Cause: java.sql.SQLException: connection disabled

; uncategorized SQLException; SQL state [null]; error code [0]; connection disabled; nested exception is java.sql.SQLException: connection disabled、