| Bug #21373 | Old tables with '@' in their name cannot be opened | ||
|---|---|---|---|
| Submitted: | 31 Jul 2006 20:46 | Modified: | 12 Dec 2007 22:04 |
| Reporter: | Ingo Strüwing | Email Updates: | |
| Status: | Closed | Impact on me: | |
| Category: | MySQL Server: Charsets | Severity: | S2 (Serious) |
| Version: | 5.1.12 | OS: | Linux (Linux) |
| Assigned to: | Alexander Barkov | CPU Architecture: | Any |
[2 Aug 2006 14:22]
Sergei Golubchik
One of the bugs here - there was never an intention to let #mysql50# to allow _creation_ of new tables, it was only implelented to support reading of old tables.
[2 Aug 2006 14:30]
Sergei Golubchik
The check for '@' is also wrong. Probably it must be
if (!strchr(share->path.str, '@'))
goto err_not_open;
[25 Sep 2006 6:01]
Alexander Barkov
This is intentional behavior, added when fixing bug#17142. We don't try to open old file names having '@' - not to confuse with a new 5.1 encoded name. One must run "mysql_upgrade" to make these old tables available. IRC log from discussion with Monty: Mar 02 16:16:32 monty> How about making it easy so that if a name contains @ monty> then you don't try to reopen it with the old name monty> This will still ensure that things works for most users monty> when they emigrate and people with @ in their table names monty> must run the upgrade script
[25 Sep 2006 13:01]
Sergei Golubchik
Still the second bug - one can create a table using #mysql50# prefix to bypass encoding - still exists. The correct behaviour should be - #mysql50# prefix in create table is encoded, it has no special treatment.
[2 Oct 2007 10:32]
Alexander Barkov
Agreed that this is not a bug. Setting to "Documenting". To doc team: Please consider documenting two things in 5.1 manual: 1. the prefix "#mysql50#" in table names has its own special meaning and one should never use names with this prefix in CREATE TABLE. 2. when upgrading from 5.0 to 5.1, old tables having '@' sign in their names may not be opened by 5.1 server, so they should be dumped and restored.
[12 Dec 2007 22:04]
Paul DuBois
I have added Bar's suggested notes (from [2 Oct 12:32] entry) to the manual. They will appear here: http://dev.mysql.com/doc/refman/5.1/en/identifier-mapping.html http://dev.mysql.com/doc/refman/5.1/en/upgrading-from-5-0.html
Description: Tables from pre-5.1 with a '@' in their name cannot be opened unless prefixed with '#mysql50#'. The below test result shows the misbehaviour: ! DROP TABLE IF EXISTS `t@1`, `#mysql50#t%1`, `#mysql50#t@1`; ! CREATE TABLE `t@1` (c1 INT); ! INSERT INTO `t@1` VALUES (1); ! DROP TABLE `t@1`; ! CREATE TABLE `#mysql50#t%1` (c1 INT); ! INSERT INTO `t%1` VALUES (1); ! DROP TABLE `#mysql50#t%1`; ! CREATE TABLE `#mysql50#t@1` (c1 INT); ! INSERT INTO `t@1` VALUES (1); ! ERROR 42S02: Table 'test.t@1' doesn't exist ! DROP TABLE `#mysql50#t@1`; How to repeat: # For demo purposes --disable_abort_on_error # # Bug#????? - Old tables with '@' in their name cannot be opened # --disable_warnings DROP TABLE IF EXISTS `t@1`, `#mysql50#t%1`, `#mysql50#t@1`; --enable_warnings # # How everything goes with encoded name and '@' in it. CREATE TABLE `t@1` (c1 INT); INSERT INTO `t@1` VALUES (1); DROP TABLE `t@1`; # # How everything goes with non-encoded name and non-'@' in it. # Prefix '#mysql50#' suppresses encoding. Needed for create and drop. # On open encoded and non-encoded names are tried. CREATE TABLE `#mysql50#t%1` (c1 INT); INSERT INTO `t%1` VALUES (1); DROP TABLE `#mysql50#t%1`; # # Old table with '@' does not work. CREATE TABLE `#mysql50#t@1` (c1 INT); INSERT INTO `t@1` VALUES (1); DROP TABLE `#mysql50#t@1`; Suggested fix: In table.cc:open_table_def() these lines look suspicious: strxmov(path, share->normalized_path.str, reg_ext, NullS); if ((file= my_open(path, O_RDONLY | O_SHARE, MYF(0))) < 0) { if (strchr(share->table_name.str, '@')) goto err_not_open; /* Try unecoded 5.0 name */ Perhaps the check for '@' is wrong?