服务器未知运行时异常: 
### Error querying database.  Cause: com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure

The last packet successfully received from the server was 38,336 milliseconds ago.  The last packet sent successfully to the server was 38,521 milliseconds ago.
### The error may exist in file [D:\code\casic-metering\casic-metering-dao\target\classes\mapper\business\BusinessOutsourcerInfoMapper.xml]
### The error may involve defaultParameterMap
### The error occurred while setting parameters
### SQL: SELECT COUNT(*) AS total FROM business_outsourcer_info WHERE is_del = 0 AND approval_status = ? AND create_user = ?
### Cause: com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure

The last packet successfully received from the server was 38,336 milliseconds ago.  The last packet sent successfully to the server was 38,521 milliseconds ago.
; Communications link failure

The last packet successfully received from the server was 38,336 milliseconds ago.  The last packet sent successfully to the server was 38,521 milliseconds ago.; nested exception is com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure

The last packet successfully received from the server was 38,336 milliseconds ago.  The last packet sent successfully to the server was 38,521 milliseconds ago.