Opened 9 years ago
Last modified 6 years ago
#25243 new Bug
inspectdb crashes if SQLite foreign key references sqlite_master
Reported by: | Stephan Sokolow | Owned by: | nobody |
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Component: | Core (Management commands) | Version: | 1.8 |
Severity: | Normal | Keywords: | |
Cc: | dina.paolo@… | Triage Stage: | Accepted |
Has patch: | no | Needs documentation: | no |
Needs tests: | no | Patch needs improvement: | no |
Easy pickings: | no | UI/UX: | no |
Description
While trying to import an SQLite database from an old legacy codebase, I ran up against the following exception in Django 1.8.3:
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:
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:
REFERENCES sqlite_master (tbl_name) ON DELETE RESTRICT ON UPDATE CASCADE
At the very least, it should probably have a clearer error message.
Change History (4)
comment:1 by , 9 years ago
comment:2 by , 9 years ago
Triage Stage: | Unreviewed → Accepted |
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comment:3 by , 9 years ago
Cc: | added |
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comment:4 by , 6 years ago
I'm just posting a temporary test case diff (very WIP):
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tests/backends/sqlite/test_introspection.py
diff --git a/tests/backends/sqlite/test_introspection.py b/tests/backends/sqlite/test_introspection.py index 1695ee549e..6a4508031d 100644
a b class IntrospectionTests(TestCase): 25 25 self.assertEqual(field, expected_string) 26 26 finally: 27 27 cursor.execute('DROP TABLE test_primary') 28 29 def test_references_sqlite_master(self): 30 with connection.cursor() as cursor: 31 sql = ( 32 'CREATE TABLE todos (' 33 ' id INTEGER PRIMARY KEY,' 34 ' pg INTEGER REFERENCES sqlite_master (root_page)' 35 ')' 36 ) 37 res = cursor.execute(sql) 38 try: 39 relations = connection.introspection.get_relations(cursor, 'todos') 40 # What should we expect here? 41 self.assertEqual(relations, {}) 42 finally: 43 # I cannot understand why the following DROP fails (due to the FK somewhere). 44 cursor.execute('DROP TABLE todos')
I'm not sure if it's possible to find the relation in any way...
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.)