Allow db_index=False for ForeignKey
|Reported by:||Alexander Schepanovski||Owned by:||Alexander Schepanovski|
|Component:||Database layer (models, ORM)||Version:||1.2|
|Cc:||Triage Stage:||Ready for checkin|
|Has patch:||yes||Needs documentation:||no|
|Needs tests:||no||Patch needs improvement:||no|
Now db_index=True is hard-coded, so I have to drop unneeded indexes manually after syncdb or south migrate.
Indexes slow down insert, update and delete operations, so it's ineffective to manage indexes that are not really used.
They may be not used if:
- they are created for consistency not for joins;
- there are partial, multiple column or other special indexes that would be used instead of them