com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Table 'XXX' doesn't exist

org.springframework.jdbc.BadSqlGrammarException: 
### Error querying database.  Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Table 'atcrowdfunding.t_usernum' doesn't exist
### The error may exist in URL [jar:file:/E:/Yang/Desktop/select(1)/atcrowdfunding/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/Atcrowdfunding-main/WEB-INF/lib/Atcrowdfunding-manager-impl-0.0.1-SNAPSHOT.jar!/mybatis/UsernumMapper.xml]
### The error may involve com.hahah.atcrowdfunding.manager.dao.UsernumMapper.selectUsernumByDate-Inline
### The error occurred while setting parameters
### SQL: select id, usernum, time     from t_usernum     where time = ?
### Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Table 'atcrowdfunding.t_usernum' doesn't exist
; bad SQL grammar []; nested exception is com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Table 'atcrowdfunding.t_usernum' doesn't exist

异常的原因有很多，其他博客有说明，主要是说表名的大小写可能有问题

我这里再提供一个错误的原因，jdbc.config配置文件是从其他项目拷贝过来的，忘了改数据库了o(╥﹏╥)o脑子瓦特了，