id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
7877	incorrect ProgrammingError in IPython	Kenneth Arnold	nobody	"I ran into this today and couldn't debug it. There's something weird in the interaction between IPython (Ubuntu's version 0.8.1-2) and Django.

The symptom is {{{<class 'psycopg2.ProgrammingError'>: current transaction is aborted, commands ignored until end of transaction block}}} after executing a statement that throws a ''single'' SQL error. The immediate cause of that, as looking in django.db.connection.queries confirms, is that the query is actually getting run ''twice''. It only happens when not storing the output in a variable; when the statement is an assignment, the real (original) database error is displayed.

Example:
{{{
In [1]: from csamoa.conceptnet.models import *
In [4]: from django.db import connection
In [5]: connection.queries
In [6]: a=Assertion.objects.all()[0]
In [7]: connection.queries
Out[7]: 
[{'sql': 'SELECT ""predicates"".""id"", ""predicates"".""batch_id"", ""predicates"".""raw_id"", ""predicates"".""frame_id"", ""predicates"".""predtype_id"", ""predicates"".""stem1_id"", ""predicates"".""stem2_id"", ""predicates"".""polarity"", ""predicates"".""modality"", ""predicates"".""score"", ""predicates"".""created_on"", ""predicates"".""text1"", ""predicates"".""text2"", ""predicates"".""creator_id"", ""predicates"".""sentence_id"", ""predicates"".""language_id"", ""predicates"".""visible"", ""predicates"".""source"" FROM ""predicates"" ORDER BY ""predicates"".""score"" DESC LIMIT 1',
  'time': '0.005'}]
In [9]: a.creator
... traceback ... execute in db.backends.util...
<class 'psycopg2.ProgrammingError'>: current transaction is aborted, commands ignored until end of transaction block
In [10]: connection.queries
Out[10]: 
[{'sql': 'SELECT ""predicates"".""id"", ""predicates"".""batch_id"", ""predicates"".""raw_id"", ""predicates"".""frame_id"", ""predicates"".""predtype_id"", ""predicates"".""stem1_id"", ""predicates"".""stem2_id"", ""predicates"".""polarity"", ""predicates"".""modality"", ""predicates"".""score"", ""predicates"".""created_on"", ""predicates"".""text1"", ""predicates"".""text2"", ""predicates"".""creator_id"", ""predicates"".""sentence_id"", ""predicates"".""language_id"", ""predicates"".""visible"", ""predicates"".""source"" FROM ""predicates"" ORDER BY ""predicates"".""score"" DESC LIMIT 1',
  'time': '0.005'},
 {'sql': 'SELECT ""auth_user"".""id"", ""auth_user"".""username"", ""auth_user"".""first_name"", ""auth_user"".""last_name"", ""auth_user"".""email"", ""auth_user"".""password"", ""auth_user"".""is_staff"", ""auth_user"".""is_active"", ""auth_user"".""is_superuser"", ""auth_user"".""last_login"", ""auth_user"".""date_joined"" FROM ""auth_user"" WHERE ""auth_user"".""id"" = 21900 ',
  'time': '0.001'},
 {'sql': 'SELECT ""auth_user"".""id"", ""auth_user"".""username"", ""auth_user"".""first_name"", ""auth_user"".""last_name"", ""auth_user"".""email"", ""auth_user"".""password"", ""auth_user"".""is_staff"", ""auth_user"".""is_active"", ""auth_user"".""is_superuser"", ""auth_user"".""last_login"", ""auth_user"".""date_joined"" FROM ""auth_user"" WHERE ""auth_user"".""id"" = 21900 ',
  'time': '0.001'}]
}}}

but with a minor change to just the last line, we get the correct behavior:

{{{
In [5]: b=a.creator
... good traceback ... 
<class 'psycopg2.ProgrammingError'>: relation ""auth_user"" does not exist

In [6]: connection.queries
Out[6]: 
[{'sql': 'SELECT ""predicates"".""id"", ""predicates"".""batch_id"", ""predicates"".""raw_id"", ""predicates"".""frame_id"", ""predicates"".""predtype_id"", ""predicates"".""stem1_id"", ""predicates"".""stem2_id"", ""predicates"".""polarity"", ""predicates"".""modality"", ""predicates"".""score"", ""predicates"".""created_on"", ""predicates"".""text1"", ""predicates"".""text2"", ""predicates"".""creator_id"", ""predicates"".""sentence_id"", ""predicates"".""language_id"", ""predicates"".""visible"", ""predicates"".""source"" FROM ""predicates"" ORDER BY ""predicates"".""score"" DESC LIMIT 1',
  'time': '0.005'},
 {'sql': 'SELECT ""auth_user"".""id"", ""auth_user"".""username"", ""auth_user"".""first_name"", ""auth_user"".""last_name"", ""auth_user"".""email"", ""auth_user"".""password"", ""auth_user"".""is_staff"", ""auth_user"".""is_active"", ""auth_user"".""is_superuser"", ""auth_user"".""last_login"", ""auth_user"".""date_joined"" FROM ""auth_user"" WHERE ""auth_user"".""id"" = 21900 ',
  'time': '0.002'}]
}}}

This smells like an IPython bug, but I'm reporting it here because this would certainly explain all the times when I got those annoying {{{ProgrammingError}}}s for irrelevant things. Anyone else see this? Or any better clues about what to report to the ipython people?
"		closed	Database layer (models, ORM)	1.0		invalid		mmoedt@…	Unreviewed	0	0	0	0	0	0