[Django] #25243: inspectdb crashes if SQLite foreign key references sqlite_master
Django
--------------------------------------------+--------------------
Reporter: ssokolow | Owner: nobody
Type: Bug | Status: new
Component: Core (Management commands) | Version: 1.8
Severity: Normal | Keywords:
Triage Stage: Unreviewed | Has patch: 0
Easy pickings: 0 | UI/UX: 0
--------------------------------------------+--------------------
While trying to import an SQLite database from an old legacy codebase, I
ran up against the following exception in Django 1.8.3:
{{{
#!sh
ssokolow@monolith XXXXXXX [django] % python manage.py inspectdb >|
models.py
Traceback (most recent call last):
File "manage.py", line 10, in <module>
execute_from_command_line(sys.argv)
File "/home/ssokolow/.virtualenvs/XXXXXXX/local/lib/python2.7/site-
packages/django/core/management/__init__.py", line 338, in
execute_from_command_line
utility.execute()
File "/home/ssokolow/.virtualenvs/XXXXXXX/local/lib/python2.7/site-
packages/django/core/management/__init__.py", line 330, in execute
self.fetch_command(subcommand).run_from_argv(self.argv)
File "/home/ssokolow/.virtualenvs/XXXXXXX/local/lib/python2.7/site-
packages/django/core/management/base.py", line 393, in run_from_argv
self.execute(*args, **cmd_options)
File "/home/ssokolow/.virtualenvs/XXXXXXX/local/lib/python2.7/site-
packages/django/core/management/base.py", line 444, in execute
output = self.handle(*args, **options)
File "/home/ssokolow/.virtualenvs/XXXXXXX/local/lib/python2.7/site-
packages/django/core/management/commands/inspectdb.py", line 25, in handle
for line in self.handle_inspection(options):
File "/home/ssokolow/.virtualenvs/XXXXXXX/local/lib/python2.7/site-
packages/django/core/management/commands/inspectdb.py", line 64, in
handle_inspection
relations = connection.introspection.get_relations(cursor, table_name)
File "/home/ssokolow/.virtualenvs/XXXXXXX/local/lib/python2.7/site-
packages/django/db/backends/sqlite3/introspection.py", line 128, in
get_relations
result = cursor.fetchall()[0]
IndexError: list index out of range
}}}
Examining the output revealed that it was dying in a table named "todos"
and, examing that further, I discovered that inspectdb did '''not''' like
what the code was doing to partially enforce a home-built generic foreign
key constraint.
Here's the schema which caused it to fail:
{{{
#!sql
CREATE TABLE todos (
id INTEGER PRIMARY KEY,
row_id INTEGER,
table_name VARCHAR(64) DEFAULT 'stories' REFERENCES sqlite_master
(tbl_name) ON DELETE RESTRICT ON UPDATE CASCADE COLLATE NOCASE,
content TEXT NOT NULL CHECK(TRIM(content) <> '' AND TRIM(content) =
content AND content NOT LIKE '% %' AND content NOT GLOB '*[
]*')
);
}}}
I had to manually dump the database to SQL, edit out this clause in vim
(because SQLite's ALTER TABLE is so limited), and then re-create the
database before inspectdb would successfully complete:
{{{
#!sql
REFERENCES sqlite_master (tbl_name) ON DELETE RESTRICT ON UPDATE CASCADE
}}}
At the very least, it should probably have a clearer error message.
--
Ticket URL: <https://code.djangoproject.com/ticket/25243>
Django <https://code.djangoproject.com/>
The Web framework for perfectionists with deadlines.
Django
Reporter: ssokolow | Owner: nobody
Type: Bug | Status: new
commands) |
Severity: Normal | Resolution:
Keywords: | Triage Stage:
| Unreviewed
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
Changes (by ssokolow):
* needs_better_patch: => 0
* needs_tests: => 0
* needs_docs: => 0
Comment:
Oh, please note that I'll have to manually check this for updates as this
Trac installation requires some kind of authentication to access RSS
feeds.
(After many bad experiences with leaks to spammers, I've learned to not
trust Trac installations with my e-mail aliases.)
--
Ticket URL: <https://code.djangoproject.com/ticket/25243#comment:1>
Django
Reporter: ssokolow | Owner: nobody
Type: Bug | Status: new
commands) |
Severity: Normal | Resolution:
Has patch: 0 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Changes (by timgraham):
* stage: Unreviewed => Accepted
--
Ticket URL: <https://code.djangoproject.com/ticket/25243#comment:2>
Django
Reporter: ssokolow | Owner: nobody
Type: Bug | Status: new
commands) |
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Has patch: 0 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Changes (by paolodina):
* cc: dina.paolo@… (added)
--
Ticket URL: <https://code.djangoproject.com/ticket/25243#comment:3>
Django
Reporter: Stephan Sokolow | Owner: nobody
Type: Bug | Status: new
Component: Core (Management | Version: 1.8
commands) |
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Has patch: 0 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Comment (by Claude Paroz):
I'm just posting a temporary test case diff (very WIP):
{{{
#!diff
diff --git a/tests/backends/sqlite/test_introspection.py
b/tests/backends/sqlite/test_introspection.py
index 1695ee549e..6a4508031d 100644
--- a/tests/backends/sqlite/test_introspection.py
+++ b/tests/backends/sqlite/test_introspection.py
@@ -25,3 +25,20 @@ class IntrospectionTests(TestCase):
self.assertEqual(field, expected_string)
finally:
cursor.execute('DROP TABLE test_primary')
+
+ def test_references_sqlite_master(self):
+ with connection.cursor() as cursor:
+ sql = (
+ 'CREATE TABLE todos ('
+ ' id INTEGER PRIMARY KEY,'
+ ' pg INTEGER REFERENCES sqlite_master (root_page)'
+ ')'
+ )
+ res = cursor.execute(sql)
+ try:
+ relations =
connection.introspection.get_relations(cursor, 'todos')
+ # What should we expect here?
+ self.assertEqual(relations, {})
+ finally:
+ # I cannot understand why the following DROP fails (due
to the FK somewhere).
+ cursor.execute('DROP TABLE todos')
}}}
I'm not sure if it's possible to find the relation in any way...
--
Ticket URL: <https://code.djangoproject.com/ticket/25243#comment:4>