initial working solution for aliases/different db column names in basic operations

ormar/fields/base.py

@@ -64,7 +64,7 @@ class BaseField:
     @classmethod
     def get_column(cls, name: str) -> sqlalchemy.Column:
         return sqlalchemy.Column(
-            name,
+            cls.name or name,
             cls.column_type,
             *cls.constraints,
             primary_key=cls.primary_key,

ormar/fields/foreign_key.py

@@ -38,7 +38,7 @@ def ForeignKey(  # noqa CFQ002
     onupdate: str = None,
     ondelete: str = None,
 ) -> Type["ForeignKeyField"]:
-    fk_string = to.Meta.tablename + "." + to.Meta.pkname
+    fk_string = to.Meta.tablename + "." + to.get_column_alias(to.Meta.pkname)
     to_field = to.__fields__[to.Meta.pkname]
     namespace = dict(
         to=to,

ormar/fields/model_fields.py

@@ -79,7 +79,7 @@ class String(ModelFieldFactory):
                 if k not in ["cls", "__class__", "kwargs"]
             },
         }
-        kwargs['allow_blank'] = kwargs.get('nullable',  True)
+        kwargs["allow_blank"] = kwargs.get("nullable", True)
         return super().__new__(cls, **kwargs)
 
     @classmethod
@@ -145,7 +145,7 @@ class Text(ModelFieldFactory):
                 if k not in ["cls", "__class__", "kwargs"]
             },
         }
-        kwargs['allow_blank'] = kwargs.get('nullable',  True)
+        kwargs["allow_blank"] = kwargs.get("nullable", True)
         return super().__new__(cls, **kwargs)
 
     @classmethod

ormar/models/metaclass.py

@@ -124,9 +124,9 @@ def create_and_append_m2m_fk(
 ) -> None:
     column = sqlalchemy.Column(
         model.get_name(),
-        model.Meta.table.columns.get(model.Meta.pkname).type,
+        model.Meta.table.columns.get(model.get_column_alias(model.Meta.pkname)).type,
         sqlalchemy.schema.ForeignKey(
-            model.Meta.tablename + "." + model.Meta.pkname,
+            model.Meta.tablename + "." + model.get_column_alias(model.Meta.pkname),
             ondelete="CASCADE",
             onupdate="CASCADE",
         ),
@@ -223,7 +223,9 @@ def populate_meta_tablename_columns_and_pk(
     name: str, new_model: Type["Model"]
 ) -> Type["Model"]:
     tablename = name.lower() + "s"
-    new_model.Meta.tablename = new_model.Meta.tablename if hasattr(new_model.Meta, 'tablename') else tablename
+    new_model.Meta.tablename = (
+        new_model.Meta.tablename if hasattr(new_model.Meta, "tablename") else tablename
+    )
     pkname: Optional[str]
 
     if hasattr(new_model.Meta, "columns"):

ormar/models/model.py

@@ -90,13 +90,13 @@ class Model(NewBaseModel):
                     previous_table=previous_table,
                     fields=fields,
                 )
-                item[first_part] = child
+                item[model_cls.get_column_name_from_alias(first_part)] = child
             else:
                 model_cls = cls.Meta.model_fields[related].to
                 child = model_cls.from_row(
                     row, previous_table=previous_table, fields=fields
                 )
-                item[related] = child
+                item[model_cls.get_column_name_from_alias(related)] = child
 
         return item
 
@@ -113,13 +113,16 @@ class Model(NewBaseModel):
         # databases does not keep aliases in Record for postgres, change to raw row
         source = row._row if isinstance(row, Record) else row
 
-        selected_columns = cls.own_table_columns(cls, fields or [], nested=nested)
+        selected_columns = cls.own_table_columns(
+            cls, fields or [], nested=nested, use_alias=True
+        )
         for column in cls.Meta.table.columns:
-            if column.name not in item and column.name in selected_columns:
+            alias = cls.get_column_name_from_alias(column.name)
+            if alias not in item and alias in selected_columns:
                 prefixed_name = (
                     f'{table_prefix + "_" if table_prefix else ""}{column.name}'
                 )
-                item[column.name] = source[prefixed_name]
+                item[alias] = source[prefixed_name]
 
         return item
 

ormar/models/modelproxy.py

@@ -47,6 +47,20 @@ class ModelTableProxy:
                     model_dict[field] = field_value.get(target_pkname)
         return model_dict
 
+    @classmethod
+    def get_column_alias(cls, field_name: str) -> str:
+        field = cls.Meta.model_fields.get(field_name)
+        if field and field.name is not None and field.name != field_name:
+            return field.name
+        return field_name
+
+    @classmethod
+    def get_column_name_from_alias(cls, alias: str) -> str:
+        for field_name, field in cls.Meta.model_fields.items():
+            if field and field.name == alias:
+                return field_name
+        return alias  # if not found it's not an alias but actual name
+
     @classmethod
     def extract_related_names(cls) -> Set:
         related_names = set()
@@ -151,10 +165,16 @@ class ModelTableProxy:
         return other
 
     @staticmethod
-    def own_table_columns(
-        model: Type["Model"], fields: List, nested: bool = False
+    def own_table_columns(  # noqa: CCR001
+        model: Type["Model"],
+        fields: List,
+        nested: bool = False,
+        use_alias: bool = False,
     ) -> List[str]:
-        column_names = [col.name for col in model.Meta.table.columns]
+        column_names = [
+            model.get_column_name_from_alias(col.name) if use_alias else col.name
+            for col in model.Meta.table.columns
+        ]
         if not fields:
             return column_names
 
@@ -175,6 +195,11 @@ class ModelTableProxy:
             columns = column_names
 
         # always has to return pk column
-        if model.Meta.pkname not in columns:
-            columns.append(model.Meta.pkname)
+        pk_alias = (
+            model.get_column_alias(model.Meta.pkname)
+            if use_alias
+            else model.Meta.pkname
+        )
+        if pk_alias not in columns:
+            columns.append(pk_alias)
         return columns

ormar/models/newbasemodel.py

@@ -134,8 +134,9 @@ class NewBaseModel(pydantic.BaseModel, ModelTableProxy, metaclass=ModelMetaclass
     def _extract_related_model_instead_of_field(
         self, item: str
     ) -> Optional[Union["Model", List["Model"]]]:
-        if item in self._orm:
-            return self._orm.get(item)
+        alias = self.get_column_alias(item)
+        if alias in self._orm:
+            return self._orm.get(alias)
         return None
 
     def __eq__(self, other: object) -> bool:

ormar/queryset/clause.py

@@ -44,7 +44,7 @@ class QueryClause:
     ) -> Tuple[List[sqlalchemy.sql.expression.TextClause], List[str]]:
 
         if kwargs.get("pk"):
-            pk_name = self.model_cls.Meta.pkname
+            pk_name = self.model_cls.get_column_alias(self.model_cls.Meta.pkname)
             kwargs[pk_name] = kwargs.pop("pk")
 
         filter_clauses, select_related = self._populate_filter_clauses(**kwargs)

ormar/queryset/join.py

@@ -106,7 +106,9 @@ class SqlJoin:
         self.select_from = sqlalchemy.sql.outerjoin(
             self.select_from, target_table, on_clause
         )
-        self.order_bys.append(text(f"{alias}_{to_table}.{model_cls.Meta.pkname}"))
+
+        pkname_alias = model_cls.get_column_alias(model_cls.Meta.pkname)
+        self.order_bys.append(text(f"{alias}_{to_table}.{pkname_alias}"))
         self_related_fields = model_cls.own_table_columns(
             model_cls, self.fields, nested=True
         )
@@ -125,12 +127,13 @@ class SqlJoin:
         part: str,
     ) -> Tuple[str, str]:
         if join_params.prev_model.Meta.model_fields[part].virtual or is_multi:
-            to_field = model_cls.resolve_relation_field(
+            to_field = model_cls.resolve_relation_name(
                 model_cls, join_params.prev_model
             )
-            to_key = to_field.name
-            from_key = model_cls.Meta.pkname
+            to_key = model_cls.get_column_alias(to_field)
+            from_key = join_params.prev_model.get_column_alias(model_cls.Meta.pkname)
         else:
-            to_key = model_cls.Meta.pkname
-            from_key = part
+            to_key = model_cls.get_column_alias(model_cls.Meta.pkname)
+            from_key = join_params.prev_model.get_column_alias(part)
+
         return to_key, from_key

ormar/queryset/query.py

@@ -40,7 +40,8 @@ class Query:
 
     @property
     def prefixed_pk_name(self) -> str:
-        return f"{self.table.name}.{self.model_cls.Meta.pkname}"
+        pkname_alias = self.model_cls.get_column_alias(self.model_cls.Meta.pkname)
+        return f"{self.table.name}.{pkname_alias}"
 
     def build_select_expression(self) -> Tuple[sqlalchemy.sql.select, List[str]]:
         self_related_fields = self.model_cls.own_table_columns(

ormar/queryset/queryset.py

@@ -70,12 +70,29 @@ class QuerySet:
             return self.model.merge_instances_list(result_rows)  # type: ignore
         return result_rows
 
+    def _prepare_model_to_save(self, new_kwargs: dict) -> dict:
+        new_kwargs = self._remove_pk_from_kwargs(new_kwargs)
+        new_kwargs = self.model.substitute_models_with_pks(new_kwargs)
+        new_kwargs = self._populate_default_values(new_kwargs)
+        new_kwargs = self._translate_columns_to_aliases(new_kwargs)
+        return new_kwargs
+
     def _populate_default_values(self, new_kwargs: dict) -> dict:
         for field_name, field in self.model_meta.model_fields.items():
             if field_name not in new_kwargs and field.has_default():
                 new_kwargs[field_name] = field.get_default()
         return new_kwargs
 
+    def _translate_columns_to_aliases(self, new_kwargs: dict) -> dict:
+        for field_name, field in self.model_meta.model_fields.items():
+            if (
+                field_name in new_kwargs
+                and field.name is not None
+                and field.name != field_name
+            ):
+                new_kwargs[field.name] = new_kwargs.pop(field_name)
+        return new_kwargs
+
     def _remove_pk_from_kwargs(self, new_kwargs: dict) -> dict:
         pkname = self.model_meta.pkname
         pk = self.model_meta.model_fields[pkname]
@@ -278,9 +295,7 @@ class QuerySet:
     async def create(self, **kwargs: Any) -> "Model":
 
         new_kwargs = dict(**kwargs)
-        new_kwargs = self._remove_pk_from_kwargs(new_kwargs)
-        new_kwargs = self.model.substitute_models_with_pks(new_kwargs)
-        new_kwargs = self._populate_default_values(new_kwargs)
+        new_kwargs = self._prepare_model_to_save(new_kwargs)
 
         expr = self.table.insert()
         expr = expr.values(**new_kwargs)
@@ -288,7 +303,7 @@ class QuerySet:
         instance = self.model(**kwargs)
         pk = await self.database.execute(expr)
 
-        pk_name = self.model_meta.pkname
+        pk_name = self.model.get_column_alias(self.model_meta.pkname)
         if pk_name not in kwargs and pk_name in new_kwargs:
             instance.pk = new_kwargs[self.model_meta.pkname]
         if pk and isinstance(pk, self.model.pk_type()):
@@ -300,9 +315,7 @@ class QuerySet:
         ready_objects = []
         for objt in objects:
             new_kwargs = objt.dict()
-            new_kwargs = self._remove_pk_from_kwargs(new_kwargs)
-            new_kwargs = self.model.substitute_models_with_pks(new_kwargs)
-            new_kwargs = self._populate_default_values(new_kwargs)
+            new_kwargs = self._prepare_model_to_save(new_kwargs)
             ready_objects.append(new_kwargs)
 
         expr = self.table.insert()

ormar/relations/relation_proxy.py

@@ -39,7 +39,7 @@ class RelationProxy(list):
 
     def _set_queryset(self) -> "QuerySet":
         owner_table = self.relation._owner.Meta.tablename
-        pkname = self.relation._owner.Meta.pkname
+        pkname = self.relation._owner.get_column_alias(self.relation._owner.Meta.pkname)
         pk_value = self.relation._owner.pk
         if not pk_value:
             raise RelationshipInstanceError(

tests/test_aliases.py

@@ -0,0 +1,95 @@
+import databases
+import pytest
+import sqlalchemy
+
+import ormar
+from tests.settings import DATABASE_URL
+
+database = databases.Database(DATABASE_URL, force_rollback=True)
+metadata = sqlalchemy.MetaData()
+
+
+class Child(ormar.Model):
+    class Meta:
+        tablename = "children"
+        metadata = metadata
+        database = database
+
+    id: ormar.Integer(name='child_id', primary_key=True)
+    first_name: ormar.String(name='fname', max_length=100)
+    last_name: ormar.String(name='lname', max_length=100)
+    born_year: ormar.Integer(name='year_born')
+
+
+class ArtistChildren(ormar.Model):
+    class Meta:
+        tablename = "children_x_artists"
+        metadata = metadata
+        database = database
+
+
+class Artist(ormar.Model):
+    class Meta:
+        tablename = "artists"
+        metadata = metadata
+        database = database
+
+    id: ormar.Integer(name='artist_id', primary_key=True)
+    first_name: ormar.String(name='fname', max_length=100)
+    last_name: ormar.String(name='lname', max_length=100)
+    born_year: ormar.Integer(name='year')
+    children: ormar.ManyToMany(Child, through=ArtistChildren)
+
+
+class Album(ormar.Model):
+    class Meta:
+        tablename = "music_albums"
+        metadata = metadata
+        database = database
+
+    id: ormar.Integer(name='album_id', primary_key=True)
+    name: ormar.String(name='album_name', max_length=100)
+    artist: ormar.ForeignKey(Artist, name='artist_id')
+
+
+@pytest.fixture(autouse=True, scope="module")
+def create_test_database():
+    engine = sqlalchemy.create_engine(DATABASE_URL)
+    metadata.drop_all(engine)
+    metadata.create_all(engine)
+    yield
+    metadata.drop_all(engine)
+
+
+def test_table_structure():
+    assert 'album_id' in [x.name for x in Album.Meta.table.columns]
+    assert 'album_name' in [x.name for x in Album.Meta.table.columns]
+    assert 'fname' in [x.name for x in Artist.Meta.table.columns]
+    assert 'lname' in [x.name for x in Artist.Meta.table.columns]
+    assert 'year' in [x.name for x in Artist.Meta.table.columns]
+
+
+@pytest.mark.asyncio
+async def test_working_with_aliases():
+    async with database:
+        async with database.transaction(force_rollback=True):
+            artist = await Artist.objects.create(first_name='Ted', last_name='Mosbey', born_year=1975)
+            await Album.objects.create(name="Aunt Robin", artist=artist)
+
+            await artist.children.create(first_name='Son', last_name='1', born_year=1990)
+            await artist.children.create(first_name='Son', last_name='2', born_year=1995)
+
+            album = await Album.objects.select_related('artist').first()
+            assert album.artist.last_name == 'Mosbey'
+
+            assert album.artist.id is not None
+            assert album.artist.first_name == 'Ted'
+            assert album.artist.born_year == 1975
+
+            assert album.name == 'Aunt Robin'
+
+            artist = await Artist.objects.select_related('children').get()
+            assert len(artist.children) == 2
+            assert artist.children[0].first_name == 'Son'
+            assert artist.children[1].last_name == '2'
+