-- 查询mysql 数据库链接空闲时间持有最大空闲时间,单位为秒 SHOW VARIABLES WHERE VAriable_name = 'interactive_timeout'; -- 会出现wait_timeout与该参数意思相近,修改时,一起修改 SHOW VARIABLES WHERE VAriable_name = '%timeout'; -- 解决问题 com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Commun…

很长的报错,截取   ERROR c.a.d.p.DruidDataSource - discard connection   com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure       The last packet successfully received from the server was 44,866 milliseconds ago. The last pac…

报错: MySQL第二天早上第一次连接超时报错, com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure 原因: 上述问题是由mysql5数据库的配置引起的.mysql5将其连接的等待时间(wait_timeout .interactive_timeout)缺省为8小时.在其客户程序中可以这样来查看其值: mysql> show global variables like 'wait…

最近在搞一个Spring boot + Mybatis + Mysql的项目,用Mybatis访问数据库时,报了如下的错误,先在网上搜索了,试了各种办法都不行, 奇葩的是,连接另外1个数据库又没问题.  最后发现是因为Mybatis的Mapper.xml文件中的SQL语句后面,多了个分号[;],导致SQL查询要等待很久,直到返回下面的报错. com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link f…

2019-11-22 17:15:27,705 FATAL [IPC Server handler 13 on 44844] org.apache.hadoop.mapred.TaskAttemptListenerImpl: Task: attempt_1574410493054_0011_m_000000_0 - exited : java.lang.RuntimeException: java.lang.RuntimeException: com.mysql.jdbc.exceptions.…

感谢大佬:https://blog.csdn.net/a704397849/article/details/93797529 springboot + mybatis多数据库 + druid连接池配置成功.正常运行后,访问第一个数据库后访问第二个数据库,再去访问第一个数据库 会报错: Error querying database. Cause: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications lin…

09:00:30.307 [http-8080-6] ERROR org.hibernate.transaction.JDBCTransaction -JDBC begin failed com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure The last packet successfully received from the server was 56,237,340 mi…

不多说,直接上干货! 问题详情 [hadoop@bigdatamaster oozie--cdh5.5.4]$ bin/ooziedb.sh create -sqlfile oozie.sql -run DB Connection [hadoop@bigdatamaster oozie--cdh5.5.4]$ bin/ooziedb.sh create -sqlfile oozie.sql -run DB Connection setting CATALINA_OPTS="$CATALINA_O…

异常描述 这个异常通常有如下信息: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure The last packet successfully received from the server was 59,977 milliseconds ago. The last packet sent successfully to the server was 1 millisecon…

1.使用sqoop技术将mysql的数据导入到Hive出现的错误如下所示: 第一次使用命令如下所示: [hadoop@slaver1 sqoop--cdh5.3.6]$ bin/sqoop import --connect jdbc:mysql://localhost:3306/test --username root --password 123456 --table tb_user --hive-import --m 1 Warning: /home/hadoop/soft/sqoop--c…