#5191 closed (invalid)
Handle "None" when type is <type: 'str'>
| Reported by: | Owned by: | Adrian Holovaty | |
|---|---|---|---|
| Component: | Database layer (models, ORM) | Version: | dev |
| Severity: | Keywords: | None NoneType str String | |
| Cc: | Triage Stage: | Unreviewed | |
| Has patch: | no | Needs documentation: | no |
| Needs tests: | no | Patch needs improvement: | no |
| Easy pickings: | no | UI/UX: | no |
Description
Apparently at least pysqlite 2.3.5 (with Python 2.5) returns "None" (<type: 'str'>) instead of None (<type: 'NoneType'>) when a field is NULL. This causes problems with Django when conditional statement compares solely to NoneType and passes string values. Fortunately this is easily fixed: if the conditional statement (if not s: return None) on db/backends/util.py line 73 is added another condition to satisfy str type "None" (if not s or s == "None": return None).
Change History (3)
comment:1 by , 18 years ago
| Resolution: | → invalid |
|---|---|
| Status: | new → closed |
comment:2 by , 18 years ago
You are correct. There was indeed one entry that for some reason had "None" instead of a valid value. Thank you very much, problem solved.
comment:3 by , 18 years ago
For some reason this problem did not occur before I updated my system to Python 2.5, therefor I was hesitant to blame upgraded pysqlite.
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I don't think you are diagnosing the right problem here. Python 2.5's built-in SQLite wrapper does not return the string "None" in these cases. I have a lot of models lying around with NULL entries and Python 2.5 returns them all correctly (using Django's current code).
Use the sqlite3 command line tool to have a look at your database tables. I think you will find they contain the string "None" for some reason.