数据库连接异常java.sql.SQLException: Unknown character set index for field '224' received from server. 2018-11-13 11:18:14 执行存储过程 actual_time_base(2018-11-13) Exception in thread "main" java.lang.NullPointerException at cn.com.letang.databaseConnection.DatabaseManager.query2(DatabaseManager.java:109) at cn.com.letang.MainManager.run(MainManager.java:139) at cn.com.letang.MainManager.main(MainManager.java:94) 登陆数据库 mysql> show variables like "%character%"; +--------------------------+----------------------------+ | Variable_name | Value | +--------------------------+----------------------------+ | character_set_client | utf8mb4 | | character_set_connection | utf8mb4 | | character_set_database | utf8mb4 | | character_set_filesystem | binary | | character_set_results | utf8mb4 | | character_set_server | utf8mb4 | | character_set_system | utf8 | | character_sets_dir | /opt/mysql/share/charsets/ | +--------------------------+----------------------------+ 8 rows in set (0.00 sec)
上面的报错，是由于MySQL的字符集导致，修改为my.cnf的字符集为utf8，然后在重启MySQL服务，就OK了。