升级数据库后突然就连接不上，错误信息如下：
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 at oracle.jdbc.driver.SQLStateMapping.newSQLException(SQLStateMapping.java:70) at oracle.jdbc.driver.DatabaseError.newSQLException(DatabaseError.java:131) at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:197) at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:525) at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:413) at oracle.jdbc.driver.PhysicalConnection.<init>(PhysicalConnection.java:508) at oracle.jdbc.driver.T4CConnection.<init>(T4CConnection.java:203) at oracle.jdbc.driver.T4CDriverExtension.getConnection(T4CDriverExtension.java:33) at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:510) at java.sql.DriverManager.getConnection(DriverManager.java:571) at java.sql.DriverManager.getConnection(DriverManager.java:187)
问题根源是不同版本数据库 Url 的写法有所不同，修改成当前数据库正确的写法即可：
老格式： jdbc:oracle:thin:@192.168.1.110:1521:ORCL 新格式： jdbc:oracle:thin:@192.168.1.110:1521/ORCL
