Opened 14 months ago
Closed 14 months ago
#34824 closed Cleanup/optimization (fixed)
Migrations generates two records when ForeignObject.to_fields/from_fields is not a tuple.
Reported by: | puc_dong | Owned by: | puc_dong |
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Component: | Migrations | Version: | 4.2 |
Severity: | Normal | Keywords: | |
Cc: | Triage Stage: | Ready for checkin | |
Has patch: | yes | Needs documentation: | no |
Needs tests: | no | Patch needs improvement: | no |
Easy pickings: | no | UI/UX: | no |
Description (last modified by )
Our data platform involves many tables and uses a lot of ForeignObject fields. Many tables do not have foreign key associations. We found that if from_fields or to_fields is configured as an array type, without changing the table structure, if makemigrations is executed, a new migration record will be generated twice.
In the first generated migration file, from_fields and to_fields are both array types, and generate_altered_fields will type-convert the from_fields and to_fields values under the current Model ForeignObject field into tuple types. Resulting in inconsistent comparisons and generating new migration file records
from_fields = getattr(new_field, "from_fields", None) if from_fields: from_rename_key = (app_label, model_name) new_field.from_fields = tuple( [ self.renamed_fields.get( from_rename_key + (from_field,), from_field ) for from_field in from_fields ] ) new_field.to_fields = tuple( [ self.renamed_fields.get(rename_key + (to_field,), to_field) for to_field in new_field.to_fields ] ) ... if old_field_dec != new_field_dec and old_field_name == field_name: ... AlterField...
No error will be reported the third time, because the second makemigrations will be saved as tuple types into the migration file, which will be consistent with the next conversion.
operation record:
https://github.com/RelaxedDong/Images/assets/38744096/513e7021-bc2f-4f7e-aa51-188cdebceb00
https://github.com/RelaxedDong/Images/assets/38744096/3be6e3b9-ec0c-4fa8-9fd9-bd04082747c9
https://github.com/RelaxedDong/Images/assets/38744096/445fdd17-6c69-4e48-bb38-be9c11defe1b
I try to solve this problem:https://github.com/django/django/pull/17238
Change History (4)
comment:1 by , 14 months ago
Description: | modified (diff) |
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comment:2 by , 14 months ago
Component: | Database layer (models, ORM) → Migrations |
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Owner: | changed from | to
Status: | new → assigned |
Summary: | If to_fields or from_fields of ForeignObject is an array type, two migration records will be generated. → Migrations generates two records when ForeignObject.to_fields/from_fields is not a tuple. |
Triage Stage: | Unreviewed → Accepted |
comment:3 by , 14 months ago
Triage Stage: | Accepted → Ready for checkin |
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comment:4 by , 14 months ago
Resolution: | → fixed |
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Status: | assigned → closed |
In 9381700: