diff options
| -rw-r--r-- | django/db/backends/base/schema.py | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/django/db/backends/base/schema.py b/django/db/backends/base/schema.py index 8cd5e11bbf..61f88401ab 100644 --- a/django/db/backends/base/schema.py +++ b/django/db/backends/base/schema.py @@ -569,7 +569,11 @@ class BaseDatabaseSchemaEditor: """Perform a "physical" (non-ManyToMany) field update.""" # Drop any FK constraints, we'll remake them later fks_dropped = set() - if old_field.remote_field and old_field.db_constraint: + if ( + self.connection.features.supports_foreign_keys and + old_field.remote_field and + old_field.db_constraint + ): fk_names = self._constraint_names(model, [old_field.column], foreign_key=True) if strict and len(fk_names) != 1: raise ValueError("Found wrong number (%s) of foreign key constraints for %s.%s" % ( @@ -599,7 +603,7 @@ class BaseDatabaseSchemaEditor: # Drop incoming FK constraints if the field is a primary key or unique, # which might be a to_field target, and things are going to change. drop_foreign_keys = ( - ( + self.connection.features.supports_foreign_keys and ( (old_field.primary_key and new_field.primary_key) or (old_field.unique and new_field.unique) ) and old_type != new_type @@ -782,7 +786,7 @@ class BaseDatabaseSchemaEditor: for sql, params in other_actions: self.execute(sql, params) # Does it have a foreign key? - if (new_field.remote_field and + if (self.connection.features.supports_foreign_keys and new_field.remote_field and (fks_dropped or not old_field.remote_field or not old_field.db_constraint) and new_field.db_constraint): self.execute(self._create_fk_sql(model, new_field, "_fk_%(to_table)s_%(to_column)s")) |