Installing MySQL-python on mac

问题

I am using OSX 10.8 and PyCharm to work on a Python development project. I have installed MySQL-python for the mac using the instructions on the website

http://blog.infoentropy.com/MySQL-python_EnvironmentError_mysql_config_not_found

However, running the project gives me this error:

django.core.exceptions.ImproperlyConfigured: Error loading MySQLdb module: dlopen(/Users/ashishagarwal/.python-eggs/MySQL_python-1.2.3-py2.7-macosx-10.6-intel.egg-tmp/_mysql.so, 2): Symbol not found: _mysql_affected_rows
  Referenced from: /Users/ashishagarwal/.python-eggs/MySQL_python-1.2.3-py2.7-macosx-10.6-intel.egg-tmp/_mysql.so
  Expected in: flat namespace
 in /Users/ashishagarwal/.python-eggs/MySQL_python-1.2.3-py2.7-macosx-10.6-intel.egg-tmp/_mysql.so

The file mentioned int the error exists at the location - /Users/ashishagarwal/.python-eggs/MySQL_python-1.2.3-py2.7-macosx-10.6-intel.egg-tmp/_mysql.so

The entire error message is -

/usr/local/bin/python2.7-32 /Users/ashishagarwal/Optimus/MashPotato/backend/mashpotato/manage.py testserver --addrport 8000
Running on development server
Traceback (most recent call last):
  File "/Users/ashishagarwal/Optimus/MashPotato/backend/mashpotato/manage.py", line 10, in <module>
    execute_from_command_line(sys.argv)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/django/core/management/__init__.py", line 453, in execute_from_command_line
    utility.execute()
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/django/core/management/__init__.py", line 392, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/django/core/management/__init__.py", line 272, in fetch_command
    klass = load_command_class(app_name, subcommand)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/django/core/management/__init__.py", line 77, in load_command_class
    module = import_module('%s.management.commands.%s' % (app_name, name))
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/django/utils/importlib.py", line 35, in import_module
    __import__(name)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/south/management/commands/__init__.py", line 10, in <module>
    import django.template.loaders.app_directories
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/django/template/loaders/app_directories.py", line 23, in <module>
    mod = import_module(app)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/django/utils/importlib.py", line 35, in import_module
    __import__(name)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/django/contrib/admin/__init__.py", line 3, in <module>
    from django.contrib.admin.helpers import ACTION_CHECKBOX_NAME
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/django/contrib/admin/helpers.py", line 4, in <module>
    from django.contrib.admin.util import (flatten_fieldsets, lookup_field,
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/django/contrib/admin/util.py", line 6, in <module>
    from django.db import models
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/django/db/__init__.py", line 40, in <module>
    backend = load_backend(connection.settings_dict['ENGINE'])
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/django/db/__init__.py", line 34, in __getattr__
    return getattr(connections[DEFAULT_DB_ALIAS], item)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/django/db/utils.py", line 93, in __getitem__
    backend = load_backend(db['ENGINE'])
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/django/db/utils.py", line 27, in load_backend
    return import_module('.base', backend_name)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/django/utils/importlib.py", line 35, in import_module
    __import__(name)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/django/db/backends/mysql/base.py", line 17, in <module>
    raise ImproperlyConfigured("Error loading MySQLdb module: %s" % e)
django.core.exceptions.ImproperlyConfigured: Error loading MySQLdb module: dlopen(/Users/ashishagarwal/.python-eggs/MySQL_python-1.2.3-py2.7-macosx-10.6-intel.egg-tmp/_mysql.so, 2): Symbol not found: _mysql_affected_rows
  Referenced from: /Users/ashishagarwal/.python-eggs/MySQL_python-1.2.3-py2.7-macosx-10.6-intel.egg-tmp/_mysql.so
  Expected in: flat namespace
 in /Users/ashishagarwal/.python-eggs/MySQL_python-1.2.3-py2.7-macosx-10.6-intel.egg-tmp/_mysql.so

Process finished with exit code 1

回答1:

You should install MySQL through Homebrew first, to get python-mysql work properly on OS X.

pip uninstall MySQL-python
brew install mysql
pip install MySQL-python

回答2:

Make sure you have the most recent version of Xcode including Command Line Tools. I simply downloaded the 2GB update from the app store. I had a similar problem, specifically this, and that fixed it.

Cheers!

回答3:

I installed mysql a long time ago with homebrew so when I ran into trouble now after upgrading OSX I reinstalled it again with brew reinstall mysql@5.7 (I ran 5.7.10) and reinstalled MySQL-python I expected it to be resolved. Got the error mentioned above.

It really did my head in and after spending several hours on it I had no idea what to do, rebuilt from source and everything. Tried other python apps for mysql but it was the same thing.

I somehow realised that the client being built by MySQL-python was against the wrong version so I checked where the /usr/local/opt/mysql was linked to and there it was, it was linked to a previous version which I had installed via dmg like 7 years ago! Once I removed that link and then ran brew link mysql and then created a new virtualenv and installed all the packages from scratch it finally worked!