| Bug #16291 | mysqldump corrupts string-constants with non-ascii-chars | ||
|---|---|---|---|
| Submitted: | 8 Jan 2006 23:41 | Modified: | 11 Jul 2007 19:52 |
| Reporter: | Roland Volkmann | Email Updates: | |
| Status: | Closed | Impact on me: | |
| Category: | MySQL Server: Charsets | Severity: | S2 (Serious) |
| Version: | 5.0.19-BK, 5.0.18-nt | OS: | Linux (Linux, Windows XP Prof.) |
| Assigned to: | Alexander Nozdrin | CPU Architecture: | Any |
| Tags: | rt_q1_2007 | ||
[8 Jan 2006 23:41]
Roland Volkmann
[10 Jan 2006 10:22]
Valeriy Kravchuk
Thank you for a problem report. Please, send the results of show variables like 'collat%'; and show variables like 'char%'; statements from mysql client just before create view and create procedure statements. Just to be sure...
[10 Jan 2006 10:53]
Roland Volkmann
Here are the requested infos from mysql client: mysql> create database ttt; Query OK, 1 row affected (0.05 sec) mysql> use ttt; Database changed mysql> set names cp850; Query OK, 0 rows affected (0.06 sec) mysql> show variables like 'collat%'; +----------------------+-------------------+ | Variable_name | Value | +----------------------+-------------------+ | collation_connection | cp850_general_ci | | collation_database | latin1_german2_ci | | collation_server | latin1_german2_ci | +----------------------+-------------------+ 3 rows in set (0.03 sec) mysql> show variables like 'char%'; +--------------------------+---------------------------------------------------- -+ | Variable_name | Value | +--------------------------+---------------------------------------------------- -+ | character_set_client | cp850 | | character_set_connection | cp850 | | character_set_database | latin1 | | character_set_results | cp850 | | character_set_server | latin1 | | character_set_system | utf8 | | character_sets_dir | D:\Programme\MySQL\MySQL Server 5.0\share\charsets\ | +--------------------------+---------------------------------------------------- -+ 7 rows in set (0.01 sec) mysql> And here the results of the same queries from EMS SQL Manager: Variable_name Value --------------------------------------------------------- collation_connection latin1_swedish_ci collation_database latin1_german2_ci collation_server latin1_german2_ci Variable_name Value --------------------------------------------------------- character_set_client latin1 character_set_connection latin1 character_set_database latin1 character_set_results latin1 character_set_server latin1 character_set_system utf8 character_sets_dir D:\Programme\MySQL\MySQL Server 5.0\share\charsets\ With best regards, Roland.
[21 Jan 2006 14:48]
Valeriy Kravchuk
Verified just as described with 5.0.19-BK on Linux: Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 3 to server version: 5.0.19 Type 'help;' or '\h' for help. Type '\c' to clear the buffer. mysql> create database ttt; Query OK, 1 row affected (0.00 sec) mysql> use ttt; Database changed mysql> set names cp850; Query OK, 0 rows affected (0.07 sec) mysql> create view v_test as select 'äöü'; Query OK, 0 rows affected (0.04 sec) mysql> select * from v_test; +--------+ | äöü | +--------+ | äöü | +--------+ 1 row in set (0.04 sec) mysql> create procedure p_test() select 'äöü'; Query OK, 0 rows affected (0.00 sec) mysql> call p_test(); +--------+ | äöü | +--------+ | äöü | +--------+ 1 row in set (0.00 sec) Query OK, 0 rows affected (0.03 sec) mysql> exit Bye [openxs@Fedora 5.0]$ bin/mysqldump --default-character-set=latin1 --databases ttt --routines --single-transaction --opt --user=root --result-file=ttt.sql [openxs@Fedora 5.0]$ cat ttt.sql -- MySQL dump 10.10 -- -- Host: localhost Database: ttt -- ------------------------------------------------------ -- Server version 5.0.19 /*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */; /*!40101 SET @OLD_CHARACTER_SET_RESULTS=@@CHARACTER_SET_RESULTS */; /*!40101 SET @OLD_COLLATION_CONNECTION=@@COLLATION_CONNECTION */; /*!40101 SET NAMES latin1 */; /*!40103 SET @OLD_TIME_ZONE=@@TIME_ZONE */; /*!40103 SET TIME_ZONE='+00:00' */; /*!40014 SET @OLD_UNIQUE_CHECKS=@@UNIQUE_CHECKS, UNIQUE_CHECKS=0 */; /*!40014 SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0 */; /*!40101 SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='NO_AUTO_VALUE_ON_ZERO' */; /*!40111 SET @OLD_SQL_NOTES=@@SQL_NOTES, SQL_NOTES=0 */; -- -- Current Database: `ttt` -- CREATE DATABASE /*!32312 IF NOT EXISTS*/ `ttt` /*!40100 DEFAULT CHARACTER SET latin1 */; USE `ttt`; -- -- Table structure for table `v_test` -- DROP TABLE IF EXISTS `v_test`; /*!50001 DROP VIEW IF EXISTS `v_test`*/; /*!50001 DROP TABLE IF EXISTS `v_test`*/; /*!50001 CREATE TABLE `v_test` ( `?�?�??` varchar(6) ) */; -- -- Dumping routines for database 'ttt' -- DELIMITER ;; /*!50003 DROP PROCEDURE IF EXISTS `p_test` */;; /*!50003 SET SESSION SQL_MODE=""*/;; /*!50003 CREATE PROCEDURE `p_test`() select '���' */;; /*!50003 SET SESSION SQL_MODE=@OLD_SQL_MODE*/;; DELIMITER ; -- -- Current Database: `ttt` -- CREATE DATABASE /*!32312 IF NOT EXISTS*/ `ttt` /*!40100 DEFAULT CHARACTER SET latin1 */; USE `ttt`; -- -- View structure for view `v_test` -- /*!50001 DROP TABLE IF EXISTS `v_test`*/; /*!50001 DROP VIEW IF EXISTS `v_test`*/; /*!50001 CREATE ALGORITHM=UNDEFINED DEFINER=`root`@`localhost` SQL SECURITY DEFINER VIEW `v_test` AS select _cp850'���' AS `?�?�??`*/; /*!40103 SET TIME_ZONE=@OLD_TIME_ZONE */; So, it really looks like a bug or something that should be clearly documented.
[21 Jan 2006 18:12]
Valeriy Kravchuk
Sorry, my fault. What we got is a result of charsets that were not properly set. Just skip that --default-character-set and check the results yourself. Or set it properly, according to data you are trying to dump. It is not a bug, but intended behaviour.
[23 Jan 2006 20:45]
Sergei Golubchik
It's a bug.
[12 Apr 2006 14:54]
Sergei Golubchik
test case: create view v_test as select 'äöü'; create procedure p_test() select 'äöü'; show create view v_test; show create procedure p_test; result: CREATE ALGORITHM=UNDEFINED DEFINER=`serg`@`localhost` SQL SECURITY DEFINER VIEW `v_test` AS select _latin1'???' AS `äöü` CREATE DEFINER=`serg`@`localhost` PROCEDURE `p_test`() select '???'
[10 Jul 2006 6:29]
Greg Lehey
This bug was entered against backup. As serg has shown, this is not the case. Changing to 'character sets'.
[11 Jul 2006 4:28]
Greg Lehey
Checking the code: SHOW CREATE VIEW calls mysqld_show_create() (sql_show.cc), while SHOW CREATE PROCEDURE calls sp_head::show_create_procedure() (sp_head.cc). mysqld_show_create() handles the information directly and uses the correct character set, latin1. ::show_create_procedure() calls Protocol::send_fields() (protocol.cc), which thinks that the character set is UTF. Investigation continues.
[11 Aug 2006 13:30]
Bugs System
A patch for this bug has been committed. After review, it may be pushed to the relevant source trees for release in the next version. You can access the patch from: http://lists.mysql.com/commits/10311 ChangeSet@1.2236, 2006-08-11 15:29:04+02:00, andrey@example.com +1 -0 Fix for bug#16291: mysqldump corrupts string-constants with non-ascii-chars The fix is the part related to stored procedures. There is no test case but one can use this one. set names latin1; CREATE PROCEDURE `p_test_latin1`() select "öäü"; --switch the konsole (not mysql) to utf8 to view correctly utf8 --then switch the connection to utf8 set names utf8; show create procedure p_test_latin1;
[11 Aug 2006 13:34]
Andrey Hristov
set names latin1; CREATE PROCEDURE `p_test_latin1`() select "öäü"; set names utf8; SHOW CREATE PROCEDURE `p_test_latin1`;
[1 Nov 2006 11:34]
Bugs System
A patch for this bug has been committed. After review, it may be pushed to the relevant source trees for release in the next version. You can access the patch from: http://lists.mysql.com/commits/14663 ChangeSet@1.2299, 2006-11-01 14:36:16+03:00, anozdrin@alik. +6 -0 This is a preliminary parch for fixing CREATE VIEW - part problem of BUG#16291: mysqldump corrupts string-constants with non-ascii-chars
[11 Dec 2006 19:52]
Bugs System
A patch for this bug has been committed. After review, it may be pushed to the relevant source trees for release in the next version. You can access the patch from: http://lists.mysql.com/commits/16793 ChangeSet@1.2318, 2006-12-11 22:51:35+03:00, anozdrin@booka. +4 -0 This is a preliminary patch for BUG#16291: mysqldump corrupts string-constants with non-ascii-chars. The fix is: - to store view-query in the original character set; - to store additional attributes -- original character sets (client, connection, server); - to use original character sets when parsing the view; - to add charset-columns into SHOW CREATE VIEW output; - to add charset-columns into I_S.VIEWS pseudo-table; - to update mysqldump so that it puts charset-switching statements before CREATE VIEW statement. They are required because now CREATE VIEW is in the original charset (not the mysqldump-client's character set).
[23 Jan 2007 12:57]
Alexander Nozdrin
BUG#23622 (mysqldump/mysql do not dump/show triggers with cp1251 chars) marked as a duplicate of this bug.
[27 Jun 2007 15:11]
Konstantin Osipov
See the note for Bug#11986
[28 Jun 2007 23:49]
Konstantin Osipov
Queued into 5.1-runtime
[28 Jun 2007 23:54]
Konstantin Osipov
Was also reviewed by Alexander Barkov
[28 Jun 2007 23:56]
Konstantin Osipov
ChangeSet
anozdrin/alik@ibm.|ChangeSet|20070628173454|18968 2007/06/28 21:34:54+04:00
anozdrin@ibm. +82 -0
Patch for the following bugs:
- BUG#11986: Stored routines and triggers can fail if the code
has a non-ascii symbol
- BUG#16291: mysqldump corrupts string-constants with non-ascii-chars
- BUG#19443: INFORMATION_SCHEMA does not support charsets properly
- BUG#21249: Character set of SP-var can be ignored
- BUG#25212: Character set of string constant is ignored (stored routines)
- BUG#25221: Character set of string constant is ignored (triggers)
There were a few general problems that caused these bugs:
1. Character set information of the original (definition) query for views,
triggers, stored routines and events was lost.
2. mysqldump output query in client character set, which can be
inappropriate to encode definition-query.
3. INFORMATION_SCHEMA used strings with mixed encodings to display object
definition;
1. No query-definition-character set.
In order to compile query into execution code, some extra data (such as
environment variables or the database character set) is used. The problem
here was that this context was not preserved. So, on the next load it can
differ from the original one, thus the result will be different.
The context contains the following data:
- client character set;
- connection collation (character set and collation);
- collation of the owner database;
The fix is to store this context and use it each time we parse (compile)
and execute the object (stored routine, trigger, ...).
2. Wrong mysqldump-output.
The original query can contain several encodings (by means of character set
introducers). The problem here was that we tried to convert original query
to the mysqldump-client character set.
Moreover, we stored queries in different character sets for different
objects (views, for one, used UTF8, triggers used original character set).
The solution is
- to store definition queries in the original character set;
- to change SHOW CREATE statement to output definition query in the
binary character set (i.e. without any conversion);
- introduce SHOW CREATE TRIGGER statement;
- to dump special statements to switch the context to the original one
before dumping and restore it afterwards.
Note, in order to preserve the database collation at the creation time,
additional ALTER DATABASE might be used (to temporary switch the database
collation back to the original value). In this case, ALTER DATABASE
privilege will be required. This is a backward-incompatible change.
3. INFORMATION_SCHEMA showed non-UTF8 strings
The fix is to generate UTF8-query during the parsing, store it in the object
and show it in the INFORMATION_SCHEMA.
Basically, the idea is to create a copy of the original query convert it to
UTF8. Character set introducers are removed and all text literals are
converted to UTF8.
This UTF8 query is intended to provide user-readable output. It must not be
used to recreate the object. Specialized SHOW CREATE statements should be
used for this.
The reason for this limitation is the following: the original query can
contain symbols from several character sets (by means of character set
introducers).
Example:
- original query:
CREATE VIEW v1 AS SELECT _cp1251 'Hello' AS c1;
- UTF8 query (for INFORMATION_SCHEMA):
CREATE VIEW v1 AS SELECT 'Hello' AS c1;
[2 Jul 2007 15:03]
Bugs System
Pushed into 5.0.46
[2 Jul 2007 15:05]
Bugs System
Pushed into 5.1.21-beta
[11 Jul 2007 19:52]
Paul DuBois
Noted in 5.1.21 changelog. (Description applies to Bug#11986, Bug#16291, Bug#19443, Bug#21249, Bug#25212, Bug#25221) Several issues were identified for stored programs containing non-ASCII symbols. These issues involved conversion errors due to incomplete character set information when translating these objects to and from stored format, such as: * Parsing the original object definition so that it can be stored. * Compiling the stored definition into executable form when the object is invoked. * Retrieval of object definitions from INFORMATION_SCHEMA tables. * Displaying the object definition in SHOW statements. This issue also affected mysqldump, which uses SHOW. The fix for the problems is to store character set information from the object creation context so that this information is available when the object needs to be used later. The context includes the client character set, the connection character set and collation, and the collation of the database with which the object is associated. As a result of the patch, several tables have new columns: * In the mysql database, the proc and event tables now have these columns: character_set_client, collation_connection, db_collation, body_utf8. * In INFORMATION_SCHEMA, the VIEWS table now has these columns: CHARACTER_SET_CLIENT, COLLATION_CONNECTION. The ROUTINES, TRIGGERS, and EVENT tables now have these columns: CHARACTER_SET_CLIENT, COLLATION_CONNECTION, DATABASE_COLLATION. These columns store the session values of the character_set_client and collation_connection system variables, and the collation of the database with which the object is associated. The values are those in effect at object creation time. (The saved database collation is not the value of the collation_database system variable, which applies to the default database; the database that contains the object is not necessarily the default database.) Several SHOW statements now display additional columns corresponding to the new table columns. These statements are: SHOW CREATE EVENT, SHOW CREATE FUNCTION, SHOW CREATE PROCEDURE, SHOW CREATE VIEW, SHOW EVENTS, SHOW FUNCTION STATUS, SHOW PROCEDURE STATUS, SHOW TRIGGERS.
[9 Aug 2007 13:18]
Bugs System
Pushed into 5.1.22-beta
[4 Mar 2011 14:13]
MprDave MprDave
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