Opened 9 years ago
Closed 9 years ago
#25690 closed Bug (duplicate)
Migration operations should be ordered to prevent all columns from being removed
| Reported by: | Matthew Crowson | Owned by: | nobody |
|---|---|---|---|
| Component: | Migrations | Version: | 1.8 |
| Severity: | Normal | Keywords: | mysql |
| Cc: | Triage Stage: | Unreviewed | |
| Has patch: | no | Needs documentation: | no |
| Needs tests: | no | Patch needs improvement: | no |
| Easy pickings: | no | UI/UX: | no |
Description
When a migration contains changes to all fields, and a removal of the pk field and the addition of a new pk field, the migration fails. This is due to the migrations removals before the additions. This yields the warning that an empty table should be dropped before the new fields can be added.
django.db.utils.OperationalError: (1090, "You can't delete all columns with ALTER TABLE; use DROP TABLE instead")
By moving the migration commands I was able to get the migration to perform successfully.
First: Remove the existing pk
Second: Add the new pk
Lastly: the migration commands as they were initially created.
Change History (3)
comment:1 by , 9 years ago
| Keywords: | mysql added |
|---|---|
| Summary: | Order of Migrations Commands Needs to Allow for All Field Changes → Migration operations should be ordered to prevent all columns from being removed |
comment:2 by , 9 years ago
This does indeed happen on MySQL when removing the last column from a table. The problem can be worked around by changing the order of operations in the migration.
Maybe it would be a good idea to drop and recreate the table if all columns are dropped?
I suppose this happens on MySQL?