OperationalError: (1136, "Column count doesn't match value count at row 1")

[anonymous]

I have an issue wich might result from an update to trunk and then back to 0.12.2. I had sporadically the error messag above but now I have found a reproducable constellation: When I go to Admin > Versions > add new version ; I receive the attached message. How can I fix this? Is there a way to save the content of the DB and reinstall trac? Or would this also recopy the mismatching column count?

Oops… 
Trac detected an internal error: 
OperationalError: (1136, "Column count doesn't match value count at 
row 1") 
System Information: 
User Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/ 
4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 
3.0.04506.648; .NET CLR 3.5.21022; .NET CLR 3.0.4506.2152; .NET CLR 
3.5.30729) 
Trac 0.12.2 
Babel 0.9.6 
Genshi 0.6 
mod_python 3.3.1 
MySQL server: "5.0.51a-24+lenny5-log", client: "5.1.49", thread-safe: 
1 
MySQLdb 1.2.2 
Python 2.6.6 (r266:84292, Dec 27 2010, 00:18:12) [GCC 4.4.5] 
pytz 2010b 
setuptools 0.6 
Subversion 1.6.12 (r955767) 
jQuery 1.4.2 

Python Traceback

... 
File "/usr/lib/pymodules/python2.6/MySQLdb/cursors.py", line 166, in 
execute Code fragment:Line 
161                 self.errorhandler(self, TypeError, m) 
162         except: 
163             exc, value, tb = exc_info() 
164             del tb 
165             self.messages.append((exc, value)) 
166             self.errorhandler(self, exc, value) 
167         self._executed = query 
168         if not self._defer_warnings: self._warning_check() 
169         return r 
170 
171     def executemany(self, query, args): 
Local variables:Name Value 
ListType <type 'list'> 
TupleType <type 'tuple'> 
args ('trac.ticket.api.TicketSystem.fields', 0) 
charset 'utf8' 
db <weakproxy at 0xb8d294dc to Connection at 0xb91a4fec> 
exc <class '_mysql_exceptions.OperationalError'> 
exc_info <built-in function exc_info> 
query "INSERT INTO cache VALUES 
('trac.ticket.api.TicketSystem.fields', 0)" 
self <trac.db.mysql_backend.MySQLUnicodeCursor object at 0xb933330c> 
value OperationalError(1136, "Column count doesn't match value count 
at row 1") 
...

[Christian Boos]

Well, normally we don't support downgrading.

If you managed to use Trac 0.12.x with a trac db which has been previously upgraded to 0.13dev (instead of reverting to your backup), it's because you tweaked the system table's database_version entry ;-)

That's not enough. In addition, you should manually undo all the upgrade steps. Fortunately for you that's still easy to do at this point, see ​googlegroups:trac-users:3495667118a066ac.