Developer at USI Inc, Mongolia

[ochirkhuyag]

It cannot be installed on mysql database with unicode character set. Trace is below.

Creating and Initializing Project
Failed to create environment. (1071, 'Specified key was too long; max key length is 1000 bytes')
Traceback (most recent call last):
  File "/var/lib/python-support/python2.5/trac/scripts/admin.py", line 613, in do_initenv
    options=options)
  File "/var/lib/python-support/python2.5/trac/env.py", line 124, in __init__
    self.create(options)
  File "/var/lib/python-support/python2.5/trac/env.py", line 229, in create
    DatabaseManager(self).init_db()
  File "/var/lib/python-support/python2.5/trac/db/api.py", line 69, in init_db
    connector.init_db(**args)
  File "/var/lib/python-support/python2.5/trac/db/mysql_backend.py", line 50, in init_db
    cursor.execute(stmt)
  File "/var/lib/python-support/python2.5/trac/db/util.py", line 51, in execute
    return self.cursor.execute(sql)
  File "/usr/lib/python2.5/site-packages/MySQLdb/cursors.py", line 164, in execute
    self.errorhandler(self, exc, value)
  File "/usr/lib/python2.5/site-packages/MySQLdb/connections.py", line 35, in defaulterrorhandler
    raise errorclass, errorvalue
OperationalError: (1071, 'Specified key was too long; max key length is 1000 bytes')


Unicode characters are 3 bytes in MySQL, so mysql_backend.py line 61 should be "limit = '''333''' / len(columns)", not limit = '''500''' / len(columns)

This bug is encountered when i was installing Trac on unicode mysql database.

MySQL database creation command was:

create database tracdb character set utf8 collate utf8_general_ci;

After above fix, it is installed with no errors.

[Christian Boos]

You probably didn't use the latest of the 0.10-stable branch, but rather 0.10.3, as this bug (#3676) was somehow fixed in the now released 0.10.4 version.

I say somehow because the fix is only limited to the workaround you described and some more tweaks for the key length for the specific case of the node_change table, but it should be good enough unless you have very long paths.

See MySqlDb for more information on MySQL support for Trac.