Question

我很难对我的mysql数据库进行编码。无法正确插入一些中文字符。我在Windows上使用xampp并拥有下表：

CREATE TABLE `Kanji` (
`ID`    MEDIUMINT NOT NULL PRIMARY KEY AUTO_INCREMENT,
`Kanji` VARCHAR(40) NOT NULL UNIQUE
);

以下插入不起作用：

INSERT INTO Kanji (Kanji)
VALUES ('');

当我在phpMyAdmin中检查表的内容时，它只显示一个＆＃39;？＆＃39;。插入其他汉字有效（例如＆＃39;陆＆＃39;）。

以下是我的数据库的编码设置：

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              
collation_connection     | utf8mb4_general_ci
collation_database       | utf8mb4_general_ci
collation_server         | utf8mb4_general_ci

任何想法有什么不对？

Answer 1

这与utf8无法处理4字节字符有关，如下所述：

https://dev.mysql.com/doc/refman/5.7/en/charset-unicode-utf8mb4.html

要解决这个问题，我必须：

1）运行在评论部分找到的三个ALTER语句，标记为正确答案： "Incorrect string value" when trying to insert UTF-8 into MySQL via JDBC?

（ALTER语句如下所示，在我创建的测试用例中）

2）在MySQL Workbench中设置JDBC字符集：来自https://dev.mysql.com/doc/refman/5.7/en/charset-connection.html （同样在下面的测试用例中）

----------------------------

以下是我通过MySQL Workbench创建的测试用例：

-- I was able to re-produce your case:

create table test.kanji ( col varchar(20) ) ;

INSERT INTO test.kanji (col) VALUES ('');

select * from test.kanji ;
------
? 

---- The solution:

; -- From link 1:
ALTER DATABASE test CHARACTER SET = utf8mb4 COLLATE = utf8mb4_unicode_520_ci;

ALTER TABLE test.kanji CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_520_ci;

ALTER TABLE test.kanji modify col VARCHAR(50) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_520_ci ;


-- From link 2:
set names 'utf8mb4' ; 


select * from test.kanji ;
---------
? <-- Interesting, this did not clean-up the data we inserted.

;
-- Insert a new row now that we are using utf8mb4 in the connection:
INSERT INTO test.kanji (col) VALUES ('');


select * from test.kanji ;
---------
?  <-- The first insert - still "dirty"
 <-- The second insert is correct.


-- In case you want to re-set everything back to utf8:
;
ALTER DATABASE test CHARACTER SET = utf8 COLLATE = utf8_general_ci;
ALTER TABLE test.kanji CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci;
ALTER TABLE test.kanji modify col VARCHAR(50) CHARACTER SET utf8 COLLATE utf8_general_ci ;

无法将一些中文字符插入mysql-database

1 个答案:

----------------------------