MySQL Bugs: #64205: Connected through Connector/J 5.1 to MySQL 5.5, the error message is garbled.

Bug #64205	Connected through Connector/J 5.1 to MySQL 5.5, the error message is garbled.
Submitted:	2 Feb 2012 5:21	Modified:	25 May 2012 20:43
Reporter:	Nozomu Wakamatsu	Email Updates:
Status:	Closed	Impact on me:	None
Category:	Connector / J	Severity:	S3 (Non-critical)
Version:	5.1.18	OS:	Any
Assigned to:	Alexander Soklakov	CPU Architecture:	Any
Tags:	language, lc_messages_dir, utf8

Description:
I am using the MySQL 5.5.20 and Connector/J 5.1.18.
MySQL Server is Solaris11, Connecter/J is JDK 1.7.0_02-b13 64bit on Windows7 64bit.

Issue a query from Connector/J to MySQL.
If the query fails, an error message is garbled.

Connecter/J are get the character code of the error message from "SHOW VARIABLES LIKE 'language'".
But, "language" is replaced by the "lc_messages_dir" from MySQL 5.5.
Therefore, the error message unable to get the character code, use by default character code CP1252.

How to repeat:
Cause a garbled query.
SELECT * FROM `test`.`ほげほげ`;

Result.
Caused by: com.mysql.jdbc.exceptions.MySQLSyntaxErrorException: Table 'test.??≫??’??≫??’' doesn't exist
	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1049)
	at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3609)
	at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3541)
	at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2002)
	at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2163)
	at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2624)
	at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2127)
	at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:2293)
	at jp.co.afy_systems.framework.database.wrapper.PreparedStatementWrapper.executeQuery(PreparedStatementWrapper.java:46)
	at jp.co.afy_systems.framework.database.dao.AbstractDao.executeQuery(AbstractDao.java:167)
	... 4 more

Suggested fix:
com.mysql.jdbc.CharsetMapping
1122: String errorMessageFile = conn.getServerVariable("language");
1123+ if (errorMessageFile == null) {
1124+     errorMessageFile = conn.getServerVariable("lc_messages_dir");
1125+ }

com.mysql.jdbc.ConnectionImpl
3843: query = versionComment + "SHOW VARIABLES WHERE Variable_name ='language'"
3844+         + " OR Variable_name = 'lc_messages_dir'"
3845:         + " OR Variable_name = 'net_write_timeout'"

Thank you for the bug report. Verified by code review. lc_messages_dir is not referenced anywhere in the code, so it just can not work correctly with MySQL server 5.5.

Thank you for response.

Suggested fix is an interim measure of "lc_messages_dir".
To resolve the garbled, would need to be modified further.

For example,if "errorMessageEncodingMysql" is null, return to "character_set_results".
If feasible, Should be encoded to each of column name and the error message.

When will it be fixed?

patch for cJ 5.1.20

Attachment: bug64205.diff (text/x-patch), 1.83 KiB.

Thank you for the important bug report.

I see no need to analyze "lc_messages_dir". As described in http://dev.mysql.com/doc/refman/5.5/en/charset-errors.html as of MySQL 5.5, the server constructs error messages using UTF-8 and returns them to clients in the character set specified by the character_set_results system variable. So the only need is to avoid old-style mapping (language->charset) and correctly analyze character_set_results.

Look at attached patch, please.

Thank you for the patch.

Attached a patch to Connector/J 5.1.20.
I was confirmed that the problem has been resolved.

Added to changelog for 5.1.21: 

When Connector/J was connected to a MySQL 5.5 server, the error
message for an invalid query could be returned in the wrong character
set and appear garbled.