Mybatis连接数据库时报错原因归纳

一：

报错信息

org.apache.ibatis.exceptions.PersistenceException: 

### Error querying database.  Cause: java.sql.SQLException: Listener refused the connection with the following error:

ORA-12505, TNS:listener does not currently know of SID given in connect descriptor
The Connection descriptor used by the client was:
localhost:1521:oracl

### The error may exist in sqlMapper/UsersMapper.xml

### The error may involve test.findUserById

### The error occurred while executing a query

### Cause: java.sql.SQLException: Listener refused the connection with the following error:

ORA-12505, TNS:listener does not currently know of SID given in connect descriptor

The Connection descriptor used by the client was:

localhost:1521:oracl

这里报错的可能性在于配置文件中的jdbc.url=jdbc:oracle:thin:@localhost:1521:oracl的oracl不是Oracle数据库的SID，数据库的SID是orcl，所以会报这个错，可以通过服务查看Oracle的SID进行核对