migrations.RunSQL.noop provides an easy way to create \"reversible\" Django SQL migrations, where the reverse operation does nothing (but keeps it possible to reverse back to a previous migration state without being blocked by an irreversible migration).
from django.db import migrations\n\n\nclass Migration(migrations.Migration):\n\n dependencies = [\n (\"app\", \"0114_last_migration\"),\n ]\n\n operations = [\n migrations.RunSQL(\n sql=\"\"\"\n update concordance_identifier\n set authority = replace(authority, ':', '_')\n where authority like '%:%'\n \"\"\",\n reverse_sql=migrations.RunSQL.noop,\n )\n ]