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Django Custom User UUID Duplicated (cached?)

I'm Using Django with a custom user model with custom UUID and custom user manager:
class CustomUser(AbstractUser):
id = models.UUIDField(primary_key=True, default=generate_id(), editable=False)
# ...
As you can see, I'm NOT using default=uuid4(). Instead I've made a function my on my own that uses uuid() to generate the custom id also using the timestamp:
from datetime import datetime as dt
from uuid import uuid1, uuid3, uuid4
def generate_id():
timestamp = str(dt.timestamp(dt.now()))
return uuid3(uuid4(),timestamp)
Now if I open the interactive shell: python manage.py shell and I call my function several time, this is what I get:
>>> generate_id()
UUID('bd8279f1-9b4b-3d7d-8932-f9e725f17045')
>>> generate_id()
UUID('0c2ec2ad-b062-3915-a9e9-22842c6f5ea2')
>>> generate_id()
UUID('2289202b-f252-3b27-bcae-cd44825bf4e0')
>>> generate_id()
UUID('88676ea9-4902-36ac-857d-929cb133089c')
>>> generate_id()
UUID('4a18b33e-12f0-3803-8ff0-0c4f0d1c849c')
but when I try creating 2 users:
from users.models import CustomUser
>>> one = CustomUser.objects.create_user(email='hhh#jaja.com',password='JJlsaks16112')
>>> two = CustomUser.objects.create_user(email='ttth#jija.com',password='JJlsaks16112')
Traceback (most recent call last):
File "/usr/local/lib/python3.8/site-packages/django/db/backends/utils.py", line 84, in _execute
return self.cursor.execute(sql, params)
File "/usr/local/lib/python3.8/site-packages/django/db/backends/mysql/base.py", line 73, in execute
return self.cursor.execute(query, args)
File "/usr/local/lib/python3.8/site-packages/MySQLdb/cursors.py", line 206, in execute
res = self._query(query)
File "/usr/local/lib/python3.8/site-packages/MySQLdb/cursors.py", line 319, in _query
db.query(q)
File "/usr/local/lib/python3.8/site-packages/MySQLdb/connections.py", line 259, in query
_mysql.connection.query(self, query)
MySQLdb._exceptions.IntegrityError: (1062, "Duplicate entry 'b448f583acfb31b7955926689b60f28a' for key 'PRIMARY'")
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "<console>", line 1, in <module>
File "/foodbook24-api/users/models.py", line 23, in create_user
user.save()
File "/usr/local/lib/python3.8/site-packages/django/contrib/auth/base_user.py", line 67, in save
super().save(*args, **kwargs)
File "/usr/local/lib/python3.8/site-packages/django/db/models/base.py", line 753, in save
self.save_base(using=using, force_insert=force_insert,
File "/usr/local/lib/python3.8/site-packages/django/db/models/base.py", line 790, in save_base
updated = self._save_table(
File "/usr/local/lib/python3.8/site-packages/django/db/models/base.py", line 895, in _save_table
results = self._do_insert(cls._base_manager, using, fields, returning_fields, raw)
File "/usr/local/lib/python3.8/site-packages/django/db/models/base.py", line 933, in _do_insert
return manager._insert(
File "/usr/local/lib/python3.8/site-packages/django/db/models/manager.py", line 85, in manager_method
return getattr(self.get_queryset(), name)(*args, **kwargs)
File "/usr/local/lib/python3.8/site-packages/django/db/models/query.py", line 1254, in _insert
return query.get_compiler(using=using).execute_sql(returning_fields)
File "/usr/local/lib/python3.8/site-packages/django/db/models/sql/compiler.py", line 1397, in execute_sql
cursor.execute(sql, params)
File "/usr/local/lib/python3.8/site-packages/django/db/backends/utils.py", line 98, in execute
return super().execute(sql, params)
File "/usr/local/lib/python3.8/site-packages/django/db/backends/utils.py", line 66, in execute
return self._execute_with_wrappers(sql, params, many=False, executor=self._execute)
File "/usr/local/lib/python3.8/site-packages/django/db/backends/utils.py", line 75, in _execute_with_wrappers
return executor(sql, params, many, context)
File "/usr/local/lib/python3.8/site-packages/django/db/backends/utils.py", line 84, in _execute
return self.cursor.execute(sql, params)
File "/usr/local/lib/python3.8/site-packages/django/db/utils.py", line 90, in __exit__
raise dj_exc_value.with_traceback(traceback) from exc_value
File "/usr/local/lib/python3.8/site-packages/django/db/backends/utils.py", line 84, in _execute
return self.cursor.execute(sql, params)
File "/usr/local/lib/python3.8/site-packages/django/db/backends/mysql/base.py", line 73, in execute
return self.cursor.execute(query, args)
File "/usr/local/lib/python3.8/site-packages/MySQLdb/cursors.py", line 206, in execute
res = self._query(query)
File "/usr/local/lib/python3.8/site-packages/MySQLdb/cursors.py", line 319, in _query
db.query(q)
File "/usr/local/lib/python3.8/site-packages/MySQLdb/connections.py", line 259, in query
_mysql.connection.query(self, query)
django.db.utils.IntegrityError: (1062, "Duplicate entry 'b448f583acfb31b7955926689b60f28a' for key 'PRIMARY'")
If I go into the database and modify the id of my first custom user, I'm able to create a second user but as you can see from the screenshot below, the ID does not change!
I guess is a caching issue. Anyone as any idea of how can I solve it? (possibly keeping my custom UUID function) Thanks.

You are calling the function, and therefore the default=… parameter [Django-doc] will be set to the result of the response, not the function, and thus indeed, each time you generate an object, it will use that result.
You thus should pass a reference to the callable, not the result:
class CustomUser(AbstractUser):
# no parenthesis ↓
id = models.UUIDField(primary_key=True, default=generate_id, editable=False)

flask-migrate cannot drop table because other objects depend on it

Problem applying just created migration (Added db.Model) through Flask-Migrate (SQLAlchemy) for PostgresSQL DB.
The error itself:
sqlalchemy.exc.InternalError: (psycopg2.InternalError) cannot drop table parameter_subtype because other objects depend on it
Full error stack trace is:
INFO [alembic.autogenerate.compare] Detected removed foreign key (event_id) (id) on table stage_has_event
INFO [alembic.autogenerate.compare] Detected removed column 'stage_has_event.event_id'
Generating /app/migrations/versions/e224df1a4818_.py ... done
(venv) $ ./manage db upgrade
INFO [alembic.runtime.migration] Context impl PostgresqlImpl.
INFO [alembic.runtime.migration] Will assume transactional DDL.
INFO [alembic.runtime.migration] Running upgrade cadf22871ae0 -> e224df1a4818, empty message
Traceback (most recent call last):
File "/app/venv/bin/flask", line 11, in <module>
sys.exit(main())
File "/app/venv/lib/python2.7/site-packages/flask_cli/cli.py", line 502, in main
cli.main(args=args, prog_name=name)
File "/app/venv/lib/python2.7/site-packages/flask_cli/cli.py", line 369, in main
return AppGroup.main(self, *args, **kwargs)
File "/app/venv/lib/python2.7/site-packages/click/core.py", line 697, in main
rv = self.invoke(ctx)
File "/app/venv/lib/python2.7/site-packages/click/core.py", line 1066, in invoke
return _process_result(sub_ctx.command.invoke(sub_ctx))
File "/app/venv/lib/python2.7/site-packages/click/core.py", line 1066, in invoke
return _process_result(sub_ctx.command.invoke(sub_ctx))
File "/app/venv/lib/python2.7/site-packages/click/core.py", line 895, in invoke
return ctx.invoke(self.callback, **ctx.params)
File "/app/venv/lib/python2.7/site-packages/click/core.py", line 535, in invoke
return callback(*args, **kwargs)
File "/app/venv/lib/python2.7/site-packages/click/decorators.py", line 17, in new_func
return f(get_current_context(), *args, **kwargs)
File "/app/venv/lib/python2.7/site-packages/flask/cli.py", line 257, in decorator
return __ctx.invoke(f, *args, **kwargs)
File "/app/venv/lib/python2.7/site-packages/click/core.py", line 535, in invoke
return callback(*args, **kwargs)
File "/app/venv/lib/python2.7/site-packages/flask_migrate/cli.py", line 134, in upgrade
_upgrade(directory, revision, sql, tag, x_arg)
File "/app/venv/lib/python2.7/site-packages/flask_migrate/__init__.py", line 259, in upgrade
command.upgrade(config, revision, sql=sql, tag=tag)
File "/app/venv/lib/python2.7/site-packages/alembic/command.py", line 254, in upgrade
script.run_env()
File "/app/venv/lib/python2.7/site-packages/alembic/script/base.py", line 427, in run_env
util.load_python_file(self.dir, 'env.py')
File "/app/venv/lib/python2.7/site-packages/alembic/util/pyfiles.py", line 81, in load_python_file
module = load_module_py(module_id, path)
File "/app/venv/lib/python2.7/site-packages/alembic/util/compat.py", line 141, in load_module_py
mod = imp.load_source(module_id, path, fp)
File "migrations/env.py", line 87, in <module>
run_migrations_online()
File "migrations/env.py", line 80, in run_migrations_online
context.run_migrations()
File "<string>", line 8, in run_migrations
File "/app/venv/lib/python2.7/site-packages/alembic/runtime/environment.py", line 836, in run_migrations
self.get_context().run_migrations(**kw)
File "/app/venv/lib/python2.7/site-packages/alembic/runtime/migration.py", line 330, in run_migrations
step.migration_fn(**kw)
File "/app/migrations/versions/e224df1a4818_.py", line 21, in upgrade
op.drop_table('parameter_subtype')
File "<string>", line 8, in drop_table
File "<string>", line 3, in drop_table
File "/app/venv/lib/python2.7/site-packages/alembic/operations/ops.py", line 1187, in drop_table
operations.invoke(op)
File "/app/venv/lib/python2.7/site-packages/alembic/operations/base.py", line 319, in invoke
return fn(self, operation)
File "/app/venv/lib/python2.7/site-packages/alembic/operations/toimpl.py", line 70, in drop_table
operation.to_table(operations.migration_context)
File "/app/venv/lib/python2.7/site-packages/alembic/ddl/impl.py", line 203, in drop_table
self._exec(schema.DropTable(table))
File "/app/venv/lib/python2.7/site-packages/alembic/ddl/impl.py", line 118, in _exec
return conn.execute(construct, *multiparams, **params)
File "/app/venv/lib/python2.7/site-packages/sqlalchemy/engine/base.py", line 948, in execute
return meth(self, multiparams, params)
File "/app/venv/lib/python2.7/site-packages/sqlalchemy/sql/ddl.py", line 68, in _execute_on_connection
return connection._execute_ddl(self, multiparams, params)
File "/app/venv/lib/python2.7/site-packages/sqlalchemy/engine/base.py", line 1009, in _execute_ddl
compiled
File "/app/venv/lib/python2.7/site-packages/sqlalchemy/engine/base.py", line 1200, in _execute_context
context)
File "/app/venv/lib/python2.7/site-packages/sqlalchemy/engine/base.py", line 1413, in _handle_dbapi_exception
exc_info
File "/app/venv/lib/python2.7/site-packages/sqlalchemy/util/compat.py", line 203, in raise_from_cause
reraise(type(exception), exception, tb=exc_tb, cause=cause)
File "/app/venv/lib/python2.7/site-packages/sqlalchemy/engine/base.py", line 1193, in _execute_context
context)
File "/app`enter code here`/venv/lib/python2.7/site-packages/sqlalchemy/engine/default.py", line 507, in do_execute
cursor.execute(statement, parameters)
sqlalchemy.exc.InternalError: (psycopg2.InternalError) cannot drop table parameter_subtype because other objects depend on it
DETAIL: constraint parameter_parameter_subtype_id_fkey on table parameter depends on table parameter_subtype
HINT: Use DROP ... CASCADE to drop the dependent objects too.
[SQL: '\nDROP TABLE parameter_subtype']
This leads to table not created in PostgreSQL db and columns either.
Unsure what may have caused this problem and how to understand this Error message.
I did manually drop the tables and it helped. However how to be with migration.
Any Suggestions?

Flask-Migrate does not read in the database to see the dependencies between the objects. You can achieve a successful migration by reordering the drop_table in your migration file.
What you can do is modify the migration file like so:
op.drop_table("parameter_subtype")
op.drop_table("parameter")
And then run the upgrade command. Normally ordering the drop in this order should solve the problem.

I got the same error and what worked for me was to first drop the table in the database using the command:
$ DROP TABLE table_name;
And then in the migration file in the upgrade() function delete or comment out the line where it says:
op.drop_table('table_name')

Cannot Install Fixture: file is encrypted or is not a database

I'm working on a website which allows users to nominate and vote for different positions. I use Python 2.7 and Django 1.10. The position objects were added through django's admin interface on the actual server. Therefore, my local server is empty of any positions. I wanted to add the positions to my local server for the sake of development. I ran the command python manage.py dumpdata voting.Position --=2 > voting/fixtures/default_positions.json.
The fixture has been made, and now I want to loaddata. When I run python manage.py loaddata voting/fixtures/default_positions.json (on my local dir. not the website's/server's one), I get the following error:
Traceback (most recent call last):
File "manage.py", line 22, in <module>
execute_from_command_line(sys.argv)
File "/usr/lib/python2.7/site-packages/django/core/management/__init__.py", line 367, in execute_from_command_line
utility.execute()
File "/usr/lib/python2.7/site-packages/django/core/management/__init__.py", line 359, in execute
self.fetch_command(subcommand).run_from_argv(self.argv)
File "/usr/lib/python2.7/site-packages/django/core/management/base.py", line 305, in run_from_argv
self.execute(*args, **cmd_options)
File "/usr/lib/python2.7/site-packages/django/core/management/base.py", line 356, in execute
output = self.handle(*args, **options)
File "/usr/lib/python2.7/site-packages/django/core/management/commands/loaddata.py", line 64, in handle
self.loaddata(fixture_labels)
File "/usr/lib/python2.7/site-packages/django/core/management/commands/loaddata.py", line 104, in loaddata
self.load_label(fixture_label)
File "/usr/lib/python2.7/site-packages/django/core/management/commands/loaddata.py", line 167, in load_label
obj.save(using=self.using)
File "/usr/lib/python2.7/site-packages/django/core/serializers/base.py", line 201, in save
models.Model.save_base(self.object, using=using, raw=True, **kwargs)
File "/usr/lib/python2.7/site-packages/django/db/models/base.py", line 824, in save_base
updated = self._save_table(raw, cls, force_insert, force_update, using, update_fields)
File "/usr/lib/python2.7/site-packages/django/db/models/base.py", line 889, in _save_table
forced_update)
File "/usr/lib/python2.7/site-packages/django/db/models/base.py", line 939, in _do_update
return filtered._update(values) > 0
File "/usr/lib/python2.7/site-packages/django/db/models/query.py", line 652, in _update
return query.get_compiler(self.db).execute_sql(CURSOR)
File "/usr/lib/python2.7/site-packages/django/db/models/sql/compiler.py", line 1148, in execute_sql
cursor = super(SQLUpdateCompiler, self).execute_sql(result_type)
File "/usr/lib/python2.7/site-packages/django/db/models/sql/compiler.py", line 835, in execute_sql
cursor.execute(sql, params)
File "/usr/lib/python2.7/site-packages/django/db/backends/utils.py", line 79, in execute
return super(CursorDebugWrapper, self).execute(sql, params)
File "/usr/lib/python2.7/site-packages/django/db/backends/utils.py", line 64, in execute
return self.cursor.execute(sql, params)
File "/usr/lib/python2.7/site-packages/django/db/utils.py", line 94, in __exit__
six.reraise(dj_exc_type, dj_exc_value, traceback)
File "/usr/lib/python2.7/site-packages/django/db/backends/utils.py", line 64, in execute
return self.cursor.execute(sql, params)
File "/usr/lib/python2.7/site-packages/django/db/backends/sqlite3/base.py", line 337, in execute
return Database.Cursor.execute(self, query, params)
django.db.utils.DatabaseError: Problem installing fixture '/home/Saleha/trabd/voting/fixtures/default_positions.json': Could not load voting.Position(pk=1): file is encrypted or is not a database
The fixture file: https://pastebin.com/avRzHQyf (too long for this place)
I need to say, as well, that python manage.py runserver doesn't work, nor does python manage.py makemigrations; and all that happens is that this same error pops up.
If no solution, could someone at least guide me to how to undo the loaddata command, so at least I can get my local server running I again?
I apologize for the long introduction, but I'm relatively new to programming and thought I should explain as much as I can. My error could be in the simplest and silliest of places.
Any help is appreciated. Thank you in advance.

sqlalchemy exception mysql is returning version as tuple instead of string

I have a very confusing problem with sqlalchemy. This isn't the first time I've used sqlalchemy. I'm working on a new project we just stood up from scratch, so it is possible there is a configuration error. I include the python connector package below from our pip reqs file in case it is of interest:
mysql-connector-repackaged==0.3.1
I just created a basic unit test to evaluate our sql wrapper class. The method under evaluation is an add_user class, which simply adds a user to the database. The class first runs a query to see if the user exists. This query is not succeeding.
Here is the code for the query:
q = self.session.query(User).\
filter_by(name=name, email=email)
result = q.all()
Seems simple enough, right? I'll include my connection string below in case anyone is interested:
db =create_engine('mysql+mysqlconnector://{user}:{password}#{host}:{port}/{database}'.format(user=conn.USER, password=conn.PASS, host=conn.HOST, port=conn.PORT, database=database, poolclass=NullPool))
The database is empty, although the table structure does exist. When this query is run it throws an exception. The exception reads as below:
StatementError: expected string or buffer (original cause: TypeError: expected string or buffer) u"SHOW VARIABLES LIKE 'sql_mode'" []
This exception comes from the python regular expression class re.py. The end of the stack trace looks like this:
File "/home/vagrant/GitRepos/SqlInteraction/venv/lib/python2.7/re.py", line 137, in match
return _compile(pattern, flags).match(string)
If I break on that line I can see the problem. The string object which the _compile method is running is not a string at all. It is a tuple. The tuple looks like this: (0, 3, 1, '', '')
Now, while it is obvious why that method is breaking, it is not at all obvious why a tuple is being passed in to that method. All of that happens internally to third party libraries. I include the full stack trace below for reference:
Traceback (most recent call last):
File "/home/vagrant/GitRepos/SqlInteraction/test/databasetest.py", line 14, in setUp
userId = self.add_user(Constants.TestObjects.USER_ID, Constants.TestObjects.USER_EMAIL, Constants.TestObjects.USER_PHONE)
File "/home/vagrant/GitRepos/SqlInteraction/test/databasetest.py", line 27, in add_user
result = q.all()
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/orm/query.py", line 2320, in all
return list(self)
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/orm/query.py", line 2438, in __iter__
return self._execute_and_instances(context)
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/orm/query.py", line 2451, in _execute_and_instances
close_with_result=True)
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/orm/query.py", line 2442, in _connection_from_session
**kw)
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/orm/session.py", line 854, in connection
close_with_result=close_with_result)
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/orm/session.py", line 858, in _connection_for_bind
return self.transaction._connection_for_bind(engine)
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/orm/session.py", line 322, in _connection_for_bind
conn = bind.contextual_connect()
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/engine/base.py", line 1798, in contextual_connect
self.pool.connect(),
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/pool.py", line 338, in connect
return _ConnectionFairy._checkout(self)
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/pool.py", line 644, in _checkout
fairy = _ConnectionRecord.checkout(pool)
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/pool.py", line 440, in checkout
rec = pool._do_get()
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/pool.py", line 963, in _do_get
return self._create_connection()
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/pool.py", line 285, in _create_connection
return _ConnectionRecord(self)
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/pool.py", line 416, in __init__
exec_once(self.connection, self)
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/event/attr.py", line 250, in exec_once
self(*args, **kw)
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/event/attr.py", line 260, in __call__
fn(*args, **kw)
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/util/langhelpers.py", line 1219, in go
return once_fn(*arg, **kw)
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/engine/strategies.py", line 166, in first_connect
dialect.initialize(c)
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/dialects/mysql/base.py", line 2453, in initialize
self._detect_ansiquotes(connection)
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/dialects/mysql/base.py", line 2718, in _detect_ansiquotes
connection.execute("SHOW VARIABLES LIKE 'sql_mode'"),
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/engine/base.py", line 721, in execute
return self._execute_text(object, multiparams, params)
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/engine/base.py", line 870, in _execute_text
statement, parameters
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/engine/base.py", line 893, in _execute_context
None, None)
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/engine/base.py", line 1159, in _handle_dbapi_exception
exc_info
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/util/compat.py", line 199, in raise_from_cause
reraise(type(exception), exception, tb=exc_tb)
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/engine/base.py", line 889, in _execute_context
context = constructor(dialect, self, conn, *args)
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/engine/default.py", line 635, in _init_statement
if not dialect.supports_unicode_statements and \
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/util/langhelpers.py", line 725, in __get__
obj.__dict__[self.__name__] = result = self.fget(obj)
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/dialects/mysql/mysqlconnector.py", line 97, in supports_unicode_statements
return util.py3k or self._mysqlconnector_version_info > (2, 0)
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/util/langhelpers.py", line 725, in __get__
obj.__dict__[self.__name__] = result = self.fget(obj)
File "/home/vagrant/GitRepos/SqlInteraction/venv/local/lib/python2.7/site-packages/sqlalchemy/dialects/mysql/mysqlconnector.py", line 131, in _mysqlconnector_version_info
self.dbapi.__version__)
File "/home/vagrant/GitRepos/SqlInteraction/venv/lib/python2.7/re.py", line 137, in match
return _compile(pattern, flags).match(string)
StatementError: expected string or buffer (original cause: TypeError: expected string or buffer) u"SHOW VARIABLES LIKE 'sql_mode'" []
I have no idea why this problem is occurring. I've bounced around the net with no useful results. I'm hoping someone here at SO might have some idea what is going on.

Django ORM - update() on rows multiplied with Decimal()

I need to execute a query like UPDATE sometable SET total_cost=cost*sec/60.0 via Django ORM. Query will produce some warnings similar to problems described in this ticket.
new_records = Service.objects.filter(upd='U')
print new_records.update(
total_cost=F('cost')*F('billsec')/Decimal('60.0')
)
(cost && sec fields are of DECIMAL(10,4) type).The result:
Traceback (most recent call last):
File "./test.py", line 15, in <module>
total_cost=F('cost')*F('billsec')/Decimal('60.0')
File "/usr/lib/python2.7/dist-packages/django/db/models/query.py", line 533, in update
rows = query.get_compiler(self.db).execute_sql(None)
File "/usr/lib/python2.7/dist-packages/django/db/models/sql/compiler.py", line 986, in execute_sql
cursor = super(SQLUpdateCompiler, self).execute_sql(result_type)
File "/usr/lib/python2.7/dist-packages/django/db/models/sql/compiler.py", line 818, in execute_sql
cursor.execute(sql, params)
File "/usr/lib/python2.7/dist-packages/django/db/backends/util.py", line 40, in execute
return self.cursor.execute(sql, params)
File "/usr/lib/python2.7/dist-packages/django/db/backends/mysql/base.py", line 114, in execute
return self.cursor.execute(query, args)
File "/usr/lib/python2.7/dist-packages/MySQLdb/cursors.py", line 176, in execute
if not self._defer_warnings: self._warning_check()
File "/usr/lib/python2.7/dist-packages/MySQLdb/cursors.py", line 92, in _warning_check
warn(w[-1], self.Warning, 3)
_mysql_exceptions.Warning: Data truncated for column 'total_cost' at row 1
If i'll drop Decimal() from filter query, it will work fine.

See this Django ticket
https://code.djangoproject.com/ticket/13666
It's said there that this is the problem of MySQL mishandling decimal string. Somebody said that casting decimal to float, i.e. float(Decimal('60.0')) should solve the issue.