mysql根據中文條件查詢時，報如標題的異常，其本質是：數據庫出現了兩種字符集。
SHOW VARIABLES LIKE 'character_set_%';
+--------------------------+----------------------------+
| Variable_name | Value |
+--------------------------+----------------------------+
| character_set_client | utf8|
| character_set_connection | utf8|
| character_set_database | latin1 |
| character_set_results | utf8|
| character_set_server | latin1 |
| character_set_system | utf8 |
| character_sets_dir | /home/jh/mysql/share/mysql/charsets
SHOW VARIABLES LIKE 'collation_%';
| Variable_name | Value |
+----------------------+-------------------+
| collation_connection | utf8_swedish_ci |
| collation_database | latin1_swedish_ci |
| collation_server | latin1_swedish_ci |
解決辦法：
SET character_set_database =utf8;
SET character_set_results =utf8;
SET character_set_server =utf8;
SET character_set_system =utf8; /*此處utf-8也可以*/
SET collation_server = utf8_general_ci;
SET collation_database = utf8_general_ci;
這裏有個情況需要注意，最好同時查看一下表的字符編碼，確保與庫的編碼一致，如果不一致可以通過下面的命令修改：
alter table `表名` charset=utf8;
alter table `表名` convert to character set utf8;