Develop Reference

I am trying to connect my Django app with Mysql database but when I tried to migrate loads of error started to pop up in the terminal.

I tried various ways (every solution mentioned in the stackoverflow) to solve the problem but still the problems continues.
When I run : "python manage.py migrate" the following error is shown
Traceback (most recent call last):
File "manage.py", line 22, in <module>
execute_from_command_line(sys.argv)
File "/Manish/Projects/Websites/SanirTVNetwork/SanirTV/lib/python2.7/site-packages/django/core/management/__init__.py", line 367, in execute_from_command_line
utility.execute()
File "/Manish/Projects/Websites/SanirTVNetwork/SanirTV/lib/python2.7/site-packages/django/core/management/__init__.py", line 359, in execute
self.fetch_command(subcommand).run_from_argv(self.argv)
File "/Manish/Projects/Websites/SanirTVNetwork/SanirTV/lib/python2.7/site-packages/django/core/management/base.py", line 305, in run_from_argv
self.execute(*args, **cmd_options)
File "/Manish/Projects/Websites/SanirTVNetwork/SanirTV/lib/python2.7/site-packages/django/core/management/base.py", line 353, in execute
self.check()
File "/Manish/Projects/Websites/SanirTVNetwork/SanirTV/lib/python2.7/site-packages/django/core/management/base.py", line 385, in check
include_deployment_checks=include_deployment_checks,
File "/Manish/Projects/Websites/SanirTVNetwork/SanirTV/lib/python2.7/site-packages/django/core/management/commands/migrate.py", line 61, in _run_checks
issues = run_checks(tags=[Tags.database])
File "/Manish/Projects/Websites/SanirTVNetwork/SanirTV/lib/python2.7/site-packages/django/core/checks/registry.py", line 81, in run_checks
new_errors = check(app_configs=app_configs)
File "/Manish/Projects/Websites/SanirTVNetwork/SanirTV/lib/python2.7/site-packages/django/core/checks/database.py", line 9, in check_database_backends
for conn in connections.all():
File "/Manish/Projects/Websites/SanirTVNetwork/SanirTV/lib/python2.7/site-packages/django/db/utils.py", line 226, in all
return [self[alias] for alias in self]
File "/Manish/Projects/Websites/SanirTVNetwork/SanirTV/lib/python2.7/site-packages/django/db/utils.py", line 211, in __getitem__
backend = load_backend(db['ENGINE'])
File "/Manish/Projects/Websites/SanirTVNetwork/SanirTV/lib/python2.7/site-packages/django/db/utils.py", line 115, in load_backend
return import_module('%s.base' % backend_name)
File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/importlib/__init__.py", line 37, in import_module
__import__(name)
File "/Manish/Projects/Websites/SanirTVNetwork/SanirTV/lib/python2.7/site-packages/django/db/backends/mysql/base.py", line 28, in <module>
raise ImproperlyConfigured("Error loading MySQLdb module: %s" % e)
django.core.exceptions.ImproperlyConfigured: Error loading MySQLdb module: No module named MySQLdb
Then I tried: "pip install mysql-python" as per the suggestions in the stackoverflow similar questions. I got the following error
Collecting mysql-python
Using cached MySQL-python-1.2.5.zip
Complete output from command python setup.py egg_info:
Traceback (most recent call last):
File "<string>", line 1, in <module>
File "/private/var/folders/7_/cx21vvvn5cqdypfndc7j_jl80000gn/T/pip-build-JjMQeR/mysql-python/setup.py", line 17, in <module>
metadata, options = get_config()
File "setup_posix.py", line 53, in get_config
libraries = [ dequote(i[2:]) for i in libs if i.startswith(compiler_flag("l")) ]
File "setup_posix.py", line 8, in dequote
if s[0] in "\"'" and s[0] == s[-1]:
IndexError: string index out of range
----------------------------------------
Command "python setup.py egg_info" failed with error code 1 in /private/var/folders/7_/cx21vvvn5cqdypfndc7j_jl80000gn/T/pip-build-JjMQeR/mysql-python/
I even tried: "brew install mysql-connector-c" but the same error starts to come.

I finally did it:
First I installed the command line developer tools required by running the following code inside the virtualenv
$ xcode-select --install
Then I installed MySQL-python by using the following code
pip install MySQL-python
Finally I migrated the database using:
python manage.py migrate
It worked without any errors
The main problem with the error was that I didn't installed the command line developer tools required.

Error loading psycopg2 module: dlopen with virtualenv django python 2.7

Guys I stuck this problem for couple weeks already. I have tried almost every answer I could find in stack overflow.
The error is below:
(venv1) Caimings-MacBook-Pro:yang NLStom$ python manage.py migrate
Traceback (most recent call last):
File "manage.py", line 10, in <module>
execute_from_command_line(sys.argv)
File "/Users/NLStom/Desktop/hey/yang/venv1/lib/python2.7/site-packages/django/core/management/__init__.py", line 367, in execute_from_command_line
utility.execute()
File "/Users/NLStom/Desktop/hey/yang/venv1/lib/python2.7/site-packages/django/core/management/__init__.py", line 341, in execute
django.setup()
File "/Users/NLStom/Desktop/hey/yang/venv1/lib/python2.7/site-packages/django/__init__.py", line 27, in setup
apps.populate(settings.INSTALLED_APPS)
File "/Users/NLStom/Desktop/hey/yang/venv1/lib/python2.7/site-packages/django/apps/registry.py", line 108, in populate
app_config.import_models(all_models)
File "/Users/NLStom/Desktop/hey/yang/venv1/lib/python2.7/site-packages/django/apps/config.py", line 199, in import_models
self.models_module = import_module(models_module_name)
File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/importlib/__init__.py", line 37, in import_module
__import__(name)
File "/Users/NLStom/Desktop/hey/yang/venv1/lib/python2.7/site-packages/django/contrib/auth/models.py", line 4, in <module>
from django.contrib.auth.base_user import AbstractBaseUser, BaseUserManager
File "/Users/NLStom/Desktop/hey/yang/venv1/lib/python2.7/site-packages/django/contrib/auth/base_user.py", line 52, in <module>
class AbstractBaseUser(models.Model):
File "/Users/NLStom/Desktop/hey/yang/venv1/lib/python2.7/site-packages/django/db/models/base.py", line 119, in __new__
new_class.add_to_class('_meta', Options(meta, app_label))
File "/Users/NLStom/Desktop/hey/yang/venv1/lib/python2.7/site-packages/django/db/models/base.py", line 316, in add_to_class
value.contribute_to_class(cls, name)
File "/Users/NLStom/Desktop/hey/yang/venv1/lib/python2.7/site-packages/django/db/models/options.py", line 214, in contribute_to_class
self.db_table = truncate_name(self.db_table, connection.ops.max_name_length())
File "/Users/NLStom/Desktop/hey/yang/venv1/lib/python2.7/site-packages/django/db/__init__.py", line 33, in __getattr__
return getattr(connections[DEFAULT_DB_ALIAS], item)
File "/Users/NLStom/Desktop/hey/yang/venv1/lib/python2.7/site-packages/django/db/utils.py", line 211, in __getitem__
backend = load_backend(db['ENGINE'])
File "/Users/NLStom/Desktop/hey/yang/venv1/lib/python2.7/site-packages/django/db/utils.py", line 115, in load_backend
return import_module('%s.base' % backend_name)
File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/importlib/__init__.py", line 37, in import_module
__import__(name)
File "/Users/NLStom/Desktop/hey/yang/venv1/lib/python2.7/site-packages/django/db/backends/postgresql/base.py", line 24, in <module>
raise ImproperlyConfigured("Error loading psycopg2 module: %s" % e)
django.core.exceptions.ImproperlyConfigured: Error loading psycopg2 module: dlopen(/Users/NLStom/Desktop/hey/yang/venv1/lib/python2.7/site-packages/psycopg2/_psycopg.so, 2): Symbol not found: _PQbackendPID
Referenced from: /Users/NLStom/Desktop/hey/yang/venv1/lib/python2.7/site-packages/psycopg2/_psycopg.so
Expected in: dynamic lookup
I tried to using PostgreSql for my database in Django.
Below is code in my setting
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.postgresql_psycopg2',
'NAME': 'play',
'USER': 'uaa',
'PASSWORD': '',
'HOST': 'localhost',
'PORT': '',
}
}
What have I did in PostgreSql.
psql (9.5.4)
Type "help" for help.
NLStom=# CREATE uaa;
ERROR: syntax error at or near "uaa"
LINE 1: CREATE uaa;
^
NLStom=# CREATE USER uaa;
CREATE ROLE
NLStom=# CREATE DATABASE play OWNER uaa;
CREATE DATABASE
NLStom=# \q
I used pip brew to install PostgreSql and used pip to install psycopg2.
I have done all of these above in virtualenv.
Also wanna mention that I install Postgres.app in my mac.

I got a similar error, but once I verified that psql was in my PATH and the postgres server was running in the background, I reinstalled psycopg2 with conda install psycopg2, and my django postgres app worked fine.

Got similar issue on macOS 11.01, M1 Chip.
Solved it by deleting the venv created by pycharm and recreating it manually with python3 -m venv /path/to/venv and then pip3 install -r requirements.txt.
Following github issue could be helpful.

Error loading Mysqldb module in Python Django

I am currently working on Ubuntu 14.10/Python/Django/MySQL and encountering the following error when I try to run:
$python manage.py makemigrations polls
or
$python manage.py migrate polls
I have also tried syncdb
The error is:
(Aaronpythonenv)aaron#aaron-N550JK:~/mysite$ python manage.py makemigrations polls
Traceback (most recent call last):
File "manage.py", line 10, in
execute_from_command_line(sys.argv)
File "/home/aaron/Aaronpythonenv/local/lib/python2.7/site-packages/Django-1.8-py2.7.egg/django/core/management/init.py", line 338, in execute_from_command_line
utility.execute()
File "/home/aaron/Aaronpythonenv/local/lib/python2.7/site-packages/Django-1.8-py2.7.egg/django/core/management/init.py", line 312, in execute
django.setup()
File "/home/aaron/Aaronpythonenv/local/lib/python2.7/site-packages/Django-1.8-py2.7.egg/django/init.py", line 18, in setup
apps.populate(settings.INSTALLED_APPS)
File "/home/aaron/Aaronpythonenv/local/lib/python2.7/site-packages/Django-1.8-py2.7.egg/django/apps/registry.py", line 108, in populate
app_config.import_models(all_models)
File "/home/aaron/Aaronpythonenv/local/lib/python2.7/site-packages/Django-1.8-py2.7.egg/django/apps/config.py", line 198, in import_models
self.models_module = import_module(models_module_name)
File "/usr/lib/python2.7/importlib/init.py", line 37, in import_module
import(name)
File "/home/aaron/Aaronpythonenv/local/lib/python2.7/site-packages/Django-1.8-py2.7.egg/django/contrib/auth/models.py", line 41, in
class Permission(models.Model):
File "/home/aaron/Aaronpythonenv/local/lib/python2.7/site-packages/Django-1.8-py2.7.egg/django/db/models/base.py", line 139, in new
new_class.add_to_class('_meta', Options(meta, **kwargs))
File "/home/aaron/Aaronpythonenv/local/lib/python2.7/site-packages/Django-1.8-py2.7.egg/django/db/models/base.py", line 324, in add_to_class
value.contribute_to_class(cls, name)
File "/home/aaron/Aaronpythonenv/local/lib/python2.7/site-packages/Django-1.8-py2.7.egg/django/db/models/options.py", line 250, in contribute_to_class
self.db_table = truncate_name(self.db_table, connection.ops.max_name_length())
File "/home/aaron/Aaronpythonenv/local/lib/python2.7/site-packages/Django-1.8-py2.7.egg/django/db/init.py", line 36, in getattr
return getattr(connections[DEFAULT_DB_ALIAS], item)
File "/home/aaron/Aaronpythonenv/local/lib/python2.7/site-packages/Django-1.8-py2.7.egg/django/db/utils.py", line 240, in getitem
backend = load_backend(db['ENGINE'])
File "/home/aaron/Aaronpythonenv/local/lib/python2.7/site-packages/Django-1.8-py2.7.egg/django/db/utils.py", line 111, in load_backend
return import_module('%s.base' % backend_name)
File "/usr/lib/python2.7/importlib/init.py", line 37, in import_module
import(name)
File "/home/aaron/Aaronpythonenv/local/lib/python2.7/site-packages/Django-1.8-py2.7.egg/django/db/backends/mysql/base.py", line 27, in
raise ImproperlyConfigured("Error loading MySQLdb module: %s" % e)
django.core.exceptions.ImproperlyConfigured: Error loading MySQLdb module: No module named MySQLdb
I have used PIP to install mysql-python to my environment which I recieved another error. I then used sudo apt-get command to install correct the error PIP brought up.
massive thank you in advance please let me know if I need to add anything else.

I faced somewhat similar problem. Try these steps:
1). Upgrade pip to the latest version.
sudo pip install pip --upgrade
2). Build the dependencies for python-mysqldb libraries:
sudo apt-get build-dep python-mysqldb
3). Install the Python MySQL libraries:
sudo pip install MySQL-python

I think it means there is no module named mysqldb.
You just need to setup the mysqldb module.
For example if you use the ubuntu, you just need to run this command:
sudo apt-get install python-mysqldb
and then you problem will be fixed!

Installing psycopg2 in a virtualenv in ubuntu os

I using a virtualenv and I am trying to set up postgresql. I have psycopg2 installed on my system, but it appears that my virtual env does not recognize psycopg2. Is it possible to just copy the system wide psycopg2 files into my django project directory or is this a bad approach to take?
This is the relevant part of my settings.py file in my django project.
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.postgresql_psycopg2',
'NAME': 'django_db' ,
'USER': 'myusername' ,
'PASSWORD': 'mypassword' ,
'HOST': 'localhost' ,
'PORT': '' ,
}
}
When I run python manage.py migrate I get this error:
File "manage.py", line 10, in <module>
execute_from_command_line(sys.argv)
File "/uwsgi-tutorial/local/lib/python2.7/site-packages/django/core/management/__init__.py", line 385, in execute_from_command_line
utility.execute()
File "/uwsgi-tutorial/local/lib/python2.7/site-packages/django/core/management/__init__.py", line 354, in execute
django.setup()
File "/uwsgi-tutorial/local/lib/python2.7/site-packages/django/__init__.py", line 21, in setup
apps.populate(settings.INSTALLED_APPS)
File "/uwsgi-tutorial/local/lib/python2.7/site-packages/django/apps/registry.py", line 108, in populate
app_config.import_models(all_models)
File "/uwsgi-tutorial/local/lib/python2.7/site-packages/django/apps/config.py", line 197, in import_models
self.models_module = import_module(models_module_name)
File "/usr/lib/python2.7/importlib/__init__.py", line 37, in import_module
__import__(name)
File "/uwsgi-tutorial/local/lib/python2.7/site-packages/django/contrib/auth/models.py", line 40, in <module>
class Permission(models.Model):
File "/uwsgi-tutorial/local/lib/python2.7/site-packages/django/db/models/base.py", line 125, in __new__
new_class.add_to_class('_meta', Options(meta, **kwargs))
File "/uwsgi-tutorial/local/lib/python2.7/site-packages/django/db/models/base.py", line 300, in add_to_class
value.contribute_to_class(cls, name)
File "/uwsgi-tutorial/local/lib/python2.7/site-packages/django/db/models/options.py", line 166, in contribute_to_class
self.db_table = truncate_name(self.db_table, connection.ops.max_name_length())
File "/uwsgi-tutorial/local/lib/python2.7/site-packages/django/db/__init__.py", line 40, in __getattr__
return getattr(connections[DEFAULT_DB_ALIAS], item)
File "/uwsgi-tutorial/local/lib/python2.7/site-packages/django/db/utils.py", line 242, in __getitem__
backend = load_backend(db['ENGINE'])
File "/uwsgi-tutorial/local/lib/python2.7/site-packages/django/db/utils.py", line 108, in load_backend
return import_module('%s.base' % backend_name)
File "/usr/lib/python2.7/importlib/__init__.py", line 37, in import_module
__import__(name)
File "/uwsgi-tutorial/local/lib/python2.7/site-packages/django/db/backends/postgresql_psycopg2/base.py", line 27, in <module>
raise ImproperlyConfigured("Error loading psycopg2 module: %s" % e)
django.core.exceptions.ImproperlyConfigured: Error loading psycopg2 module: No module named psycopg2
When I do pip install psycopg2 in my virtual env, I get the following error:
Exception:
Traceback (most recent call last):
File "/uwsgi-tutorial/local/lib/python2.7/site-packages/pip/basecommand.py", line 122, in main
status = self.run(options, args)
File "/uwsgi-tutorial/local/lib/python2.7/site-packages/pip/commands/install.py", line 278, in run
requirement_set.prepare_files(finder, force_root_egg_info=self.bundle, bundle=self.bundle)
File "/uwsgi-tutorial/local/lib/python2.7/site-packages/pip/req.py", line 1153, in prepare_files
location = req_to_install.build_location(self.build_dir, not self.is_download)
File "/uwsgi-tutorial/local/lib/python2.7/site-packages/pip/req.py", line 218, in build_location
_make_build_dir(build_dir)
File "/uwsgi-tutorial/local/lib/python2.7/site-packages/pip/req.py", line 1527, in _make_build_dir
os.makedirs(build_dir)
File "/uwsgi-tutorial/lib/python2.7/os.py", line 157, in makedirs
mkdir(name, mode)
OSError: [Errno 13] Permission denied: '/uwsgi-tutorial/build'
Storing debug log for failure in /home/user/.pip/pip.log

This is an old thread but some people might experience Python.h not found type of error while pip-installing psycopg2 to virtualenv on Ubuntu based systems.
Check your virtualenv python version by running python -V inside virtualenv.
Assuming it is Python 3.8.0, try installing libpython3.8-dev to your system (not virtualenv) by:
sudo apt-get install libpython3.8-dev
Probably similar approach with other versions.
That solved it for me.

Based on the combination of your question and one of your comments, it appears that when you ran sudo pip install psycopg2, it was using the system install, as it referred to psycopg2 in /usr/lib/python2.7/dist-packages which is different from the environment from which you're trying to run Django.
Your permissions error, which is from the Django environment, seems likely to be due to not using sudo (among other things, some C compilation needs to take place, during the psycopg2 install, and so sudo is often required whereas it isn't with many other packages).
I would recommend you refer to the virtualenv install's pip binary explicitly when running the sudo command.
i.e.: sudo <virtualenv_root>/bin/pip install psycopg2

Something that worked for me (python 3.8 in virtualenv):
Inside the virtual environment type:
pip install psycopg2-binary
Best.

Cannot create virtualenv instance in python 2.7.5 because of pip installation error

I'm trying to follow the directions on the Flask installation website but I encountered an error after I used "sudo easy_install virtualenv" to install virtual environment. Not sure
Opals-MacBook-Pro:~ opalkale$ mkdir myproject
Opals-MacBook-Pro:~ opalkale$ cd myproject
Opals-MacBook-Pro:myproject opalkale$ virtualenv venv
New python executable in venv/bin/python
Installing setuptools, pip...
Complete output from command /Users/opalkale/myproject/venv/bin/python -c "import sys, pip; pip...ll\"] + sys.argv[1:])" setuptools pip:
Traceback (most recent call last):
File "<string>", line 1, in <module>
File "/Library/Python/2.7/site-packages/virtualenv-1.11-py2.7.egg/virtualenv_support/pip-1.5-py2.py3-none-any.whl/pip/__init__.py", line 9, in <module>
File "/Library/Python/2.7/site-packages/virtualenv-1.11-py2.7.egg/virtualenv_support/pip-1.5-py2.py3-none-any.whl/pip/log.py", line 8, in <module>
File "/Library/Python/2.7/site-packages/virtualenv-1.11-py2.7.egg/virtualenv_support/setuptools-2.0.2-py2.py3-none-any.whl/pkg_resources.py", line 2696, in <module>
File "/Library/Python/2.7/site-packages/virtualenv-1.11-py2.7.egg/virtualenv_support/setuptools-2.0.2-py2.py3-none-any.whl/pkg_resources.py", line 429, in __init__
File "/Library/Python/2.7/site-packages/virtualenv-1.11-py2.7.egg/virtualenv_support/setuptools-2.0.2-py2.py3-none-any.whl/pkg_resources.py", line 443, in add_entry
File "/Library/Python/2.7/site-packages/virtualenv-1.11-py2.7.egg/virtualenv_support/setuptools-2.0.2-py2.py3-none-any.whl/pkg_resources.py", line 1722, in find_in_zip
File "/Library/Python/2.7/site-packages/virtualenv-1.11-py2.7.egg/virtualenv_support/setuptools-2.0.2-py2.py3-none-any.whl/pkg_resources.py", line 1298, in has_metadata
File "/Library/Python/2.7/site-packages/virtualenv-1.11-py2.7.egg/virtualenv_support/setuptools-2.0.2-py2.py3-none-any.whl/pkg_resources.py", line 1614, in _has
File "/Library/Python/2.7/site-packages/virtualenv-1.11-py2.7.egg/virtualenv_support/setuptools-2.0.2-py2.py3-none-any.whl/pkg_resources.py", line 1488, in _zipinfo_name
AssertionError: /Library/Python/2.7/site-packages/virtualenv-1.11-py2.7.egg/EGG-INFO/PKG-INFO is not a subpath of /Library/Python/2.7/site-packages/virtualenv-1.11-py2.7.egg/virtualenv_support/setuptools-2.0.2-py2.py3-none-any.whl/
----------------------------------------
...Installing setuptools, pip...done.
Traceback (most recent call last):
File "/usr/local/bin/virtualenv", line 8, in <module>
load_entry_point('virtualenv==1.11', 'console_scripts', 'virtualenv')()
File "/Library/Python/2.7/site-packages/virtualenv-1.11-py2.7.egg/virtualenv.py", line 820, in main
symlink=options.symlink)
File "/Library/Python/2.7/site-packages/virtualenv-1.11-py2.7.egg/virtualenv.py", line 988, in create_environment
install_wheel(to_install, py_executable, search_dirs)
File "/Library/Python/2.7/site-packages/virtualenv-1.11-py2.7.egg/virtualenv.py", line 956, in install_wheel
'PIP_NO_INDEX': '1'
File "/Library/Python/2.7/site-packages/virtualenv-1.11-py2.7.egg/virtualenv.py", line 898, in call_subprocess
% (cmd_desc, proc.returncode))
OSError: Command /Users/opalkale/myproject/venv/bin/python -c "import sys, pip; pip...ll\"] + sys.argv[1:])" setuptools pip failed with error code 1

This is logged as an issue with the recently released virtualenv 1.11. I had similar issues on Windows with this release.
I believe installing virtualenv 1.10.1 will let you continue working until this issue is addressed.

As timborden said in a comment: version 1.11.2 (of 2014-01-26) fixes this.
"Fixed easy_install installed virtualenvs by updated pip to 1.5.2"
See changelog at: https://pypi.python.org/pypi/virtualenv