Remove unused functions

README.md

@@ -13,6 +13,7 @@ migrations solution.
 ~~**Important: You can only use absolutely import in your `models.py` to make `aerich` work.**~~
 
 From version `v0.5.0`, there is no such limitation now.
+
 ## Install
 
 Just install from pypi:
@@ -111,7 +112,8 @@ Format of migrate filename is
 `{version_num}_{datetime}_{name|update}.sql`.
 
 And if `aerich` guess you are renaming a column, it will ask `Rename {old_column} to {new_column} [True]`, you can
-choice `True` to rename column without column drop, or choice `False` to drop column then create, note that the after maybe lose data.
+choice `True` to rename column without column drop, or choice `False` to drop column then create, note that the after
+maybe lose data.
 
 ### Upgrade to latest version
 
@@ -167,6 +169,8 @@ Now your db rollback to specified version.
 
 ### Inspect db tables to TortoiseORM model
 
+Currently, only support MySQL.
+
 ```shell
 Usage: aerich inspectdb [OPTIONS]
 

aerich/migrate.py

@@ -5,17 +5,8 @@ from typing import Dict, List, Optional, Tuple, Type
 
 import click
 from dictdiffer import diff
-from tortoise import (
+from tortoise import BaseDBAsyncClient, Model, Tortoise
-    BackwardFKRelation,
-    BackwardOneToOneRelation,
-    BaseDBAsyncClient,
-    ForeignKeyFieldInstance,
-    ManyToManyFieldInstance,
-    Model,
-    Tortoise,
-)
 from tortoise.exceptions import OperationalError
-from tortoise.fields import Field
 
 from aerich.ddl import BaseDDL
 from aerich.models import MAX_VERSION_LENGTH, Aerich
@@ -358,10 +349,6 @@ class Migrate:
             if old_model not in new_models.keys():
                 cls._add_operator(cls.remove_model(cls._get_model(old_model)), upgrade)
 
-    @classmethod
-    def _is_fk_m2m(cls, field: Field):
-        return isinstance(field, (ForeignKeyFieldInstance, ManyToManyFieldInstance))
-
     @classmethod
     def add_model(cls, model: Type[Model]):
         return cls.ddl.create_table(model)
@@ -390,29 +377,6 @@ class Migrate:
         fields_name = cls._resolve_fk_fields_name(model, fields_name)
         return cls.ddl.add_index(model, fields_name, unique)
 
-    @classmethod
-    def _exclude_field(cls, field: Field, upgrade=False):
-        """
-        exclude BackwardFKRelation and repeat m2m field
-        :param field:
-        :return:
-        """
-        if isinstance(field, ManyToManyFieldInstance):
-            through = field.through
-            if upgrade:
-                if through in cls._upgrade_m2m:
-                    return True
-                else:
-                    cls._upgrade_m2m.append(through)
-                    return False
-            else:
-                if through in cls._downgrade_m2m:
-                    return True
-                else:
-                    cls._downgrade_m2m.append(through)
-                    return False
-        return isinstance(field, (BackwardFKRelation, BackwardOneToOneRelation))
-
     @classmethod
     def _add_field(cls, model: Type[Model], field_describe: dict, is_pk: bool = False):
         return cls.ddl.add_column(model, field_describe, is_pk)