| Bug #34192 | mysqldump from mysql 5.0.51 silently fails on dumping databases from 4.0 server | ||
|---|---|---|---|
| Submitted: | 31 Jan 2008 11:45 | Modified: | 16 Apr 2008 22:42 |
| Reporter: | Arkadiusz Miskiewicz (Basic Quality Contributor) | Email Updates: | |
| Status: | Closed | Impact on me: | |
| Category: | MySQL Server: mysqldump Command-line Client | Severity: | S2 (Serious) |
| Version: | 5.0.51a | OS: | Any |
| Assigned to: | Chad MILLER | CPU Architecture: | Any |
| Tags: | Contribution, regression | ||
[31 Jan 2008 13:16]
Sveta Smirnova
Thank you for the report. Verified as described with last development sources. With verison 3.23 mysqldump works fine. This is no duplicate of bug #30444, because this is another problem and mysqldump was invoked without any options.
[31 Jan 2008 14:06]
Arkadiusz Miskiewicz
5.0.45 is also fine. The change with switch_charset... was introduced later. Bug also applies to 5.1 series.
[31 Jan 2008 18:15]
Chad MILLER
5.0 mysqldump against 4.1 mysqld works fine. Dropping to 4.0 mysqld.
[5 Feb 2008 11:49]
Arkadiusz Miskiewicz
Note that proposed "official" patch has also weaknes. If due to something switch_character_set_result() fails then still data won't be dumped and everything will happen silently.
[3 Mar 2008 15:13]
Gatis Rumbens
I was confused when suddenly my backup script doesn't work after i upgraded on backup server from 5.0.45 to 5.0.51a (mysqldump Ver 10.11 Distrib 5.0.51a). I checked several times syntax...tried to use --compatible= flag etc but no effect. i tried to dump data from: Server version: 4.0.24-standard result was only some use database; characters set etc info to create db, but no table data.
[12 Mar 2008 21:04]
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/43884 ChangeSet@1.2572, 2008-03-12 17:03:50-04:00, cmiller@zippy.cornsilk.net +1 -0 Bug#34192: mysqldump from mysql 5.0.51 silently fails on dumping \ databases from 4.0 server mysqldump treated a failure to set the results charset as a severe error. Now, don't try to set the charset for the SHOW CREATE TABLE statement, if remote server's version is earlier than 4.1, which means it doesn't support changing charsets.
[13 Mar 2008 18:01]
Chad MILLER
Queued to 5.0-build, 5.1-build, 6.0-build.
[27 Mar 2008 22:03]
Bugs System
Pushed into 5.1.24-rc
[27 Mar 2008 22:11]
Bugs System
Pushed into 5.0.60
[28 Mar 2008 11:10]
Bugs System
Pushed into 6.0.5-alpha
[16 Apr 2008 22:42]
Paul DuBois
Noted in 5.0.60, 5.1.24, 6.0.5 changelogs. mysqldump attempts to set the character_set_results system variable after connecting to the server. This failed for pre-4.1 servers that have no such variable, but mysqldump did not account for this and 1) failed to dump database contents; 2) failed to produce any error message alerting the user to the problem.
[6 May 2008 20:45]
Sveta Smirnova
Bug #36482 was marked as duplicate of this one.
Description: mysqldump in 5.0.51 SILENTLY fails to dump databases from mysql 4.0 server. The dump of any 4.0 database looks like this: -- Server version 4.0.30-log /*!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 */; /*!40103 SET TIME_ZONE=@OLD_TIME_ZONE */; HERE SHOULD BE DUMP DATA /*!40101 SET SQL_MODE=@OLD_SQL_MODE */; /*!40014 SET FOREIGN_KEY_CHECKS=@OLD_FOREIGN_KEY_CHECKS */; /*!40014 SET UNIQUE_CHECKS=@OLD_UNIQUE_CHECKS */; /*!40111 SET SQL_NOTES=@OLD_SQL_NOTES */; -- Dump completed on 2008-01-31 10:11:11 stracing reveals: 31385 write(3, "-\0\0\0\3SET SESSION character_set_results = \'binary\'", 49) = 49 31385 read(3, "2\0\0\1\377\251\4Unknown system variable \'character_set_results\'", 16384) = 54 It's because now mysqldump unconditionally runs (client/mysqldump.c): my_snprintf(buff, sizeof(buff), "show create table %s", result_table); if (switch_character_set_results(mysql, "binary") || mysql_query_with_error_report(mysql, &result, buff) || switch_character_set_results(mysql, default_charset)) DBUG_RETURN(0); where switch_character_set_results() are not supported on mysql < 4.1 How to repeat: Try using mysqldump tool from 5.0.51 on a 4.0.30 server database. Suggested fix: Ignore errors from these commands: --- mysql-5.0/client/mysqldump.c 2008-01-11 15:43:27.000000000 +0100 +++ mysql-5.0/client//mysqldump.c 2008-01-31 12:40:02.093115455 +0100 @@ -1687,10 +1687,16 @@ my_snprintf(buff, sizeof(buff), "show create table %s", result_table); - if (switch_character_set_results(mysql, "binary") || - mysql_query_with_error_report(mysql, &result, buff) || - switch_character_set_results(mysql, default_charset)) - DBUG_RETURN(0); + if (switch_character_set_results(mysql, "binary")) + if (opt_set_charset) + DBUG_RETURN(0); + + if (mysql_query_with_error_report(mysql, &result, buff)) + DBUG_RETURN(0); + + if (switch_character_set_results(mysql, default_charset)) + if (opt_set_charset) + DBUG_RETURN(0); if (path) { based on opt_set_charset.