Bump version to 0.8.0 and update changelog

tests: no need to merge operators when NotSupportError raised (#373 )
chore: upgrade deps, update changelog, drop test db before create (#372 )
2024-12-04 00:14:35 +08:00 · 2024-12-03 23:59:54 +08:00 · 2024-12-03 23:30:37 +08:00 · 2024-12-03 12:40:28 +08:00 · 2024-12-03 11:44:36 +08:00 · 2024-12-03 10:16:44 +08:00
37 changed files with 4183 additions and 1785 deletions
--- a/.github/FUNDING.yml
+++ b/.github/FUNDING.yml
@@ -0,0 +1 @@
+custom: ["https://sponsor.long2ice.io"]
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -1,7 +1,13 @@
-name: test
-on: [ push, pull_request ]
+name: ci
+on:
+  push:
+    branches-ignore:
+      - main
+  pull_request:
+    branches-ignore:
+      - main
 jobs:
-  testall:
+  ci:
    runs-on: ubuntu-latest
    services:
      postgres:
@@ -12,17 +18,26 @@ jobs:
          POSTGRES_PASSWORD: 123456
          POSTGRES_USER: postgres
        options: --health-cmd=pg_isready --health-interval 10s --health-timeout 5s --health-retries 5
+    strategy:
+      matrix:
+        python-version: ["3.8", "3.9", "3.10", "3.11", "3.12"]
    steps:
      - name: Start MySQL
        run: sudo systemctl start mysql.service
-      - uses: actions/checkout@v2
-      - uses: actions/setup-python@v2
+      - uses: actions/cache@v4
        with:
-          python-version: '3.x'
+          path: ~/.cache/pip
+          key: ${{ runner.os }}-pip-${{ hashFiles('**/poetry.lock') }}
+          restore-keys: |
+            ${{ runner.os }}-pip-
+      - uses: actions/checkout@v4
+      - uses: actions/setup-python@v5
+        with:
+          python-version: ${{ matrix.python-version }}
      - name: Install and configure Poetry
-        uses: snok/install-poetry@v1.1.1
-        with:
-          virtualenvs-create: false
+        run: |
+          pip install -U pip poetry
+          poetry config virtualenvs.create false
      - name: CI
        env:
          MYSQL_PASS: root
--- a/.github/workflows/pypi.yml
+++ b/.github/workflows/pypi.yml
@@ -7,14 +7,14 @@ jobs:
  publish:
    runs-on: ubuntu-latest
    steps:
-      - uses: actions/checkout@v2
-      - uses: actions/setup-python@v2
+      - uses: actions/checkout@v4
+      - uses: actions/setup-python@v5
        with:
          python-version: '3.x'
      - name: Install and configure Poetry
-        uses: snok/install-poetry@v1.1.1
-        with:
-          virtualenvs-create: false
+        run: |
+          pip install -U pip poetry
+          poetry config virtualenvs.create false
      - name: Build dists
        run: make build
      - name: Pypi Publish
--- a/.gitignore
+++ b/.gitignore
@@ -146,3 +146,4 @@ aerich.ini
 src
 .vscode
 .DS_Store
+.python-version
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,126 @@
 # ChangeLog

+## 0.8
+
+### [0.8.0](../../releases/tag/v0.8.0) - 2024-12-04
+
+- Fix the issue of parameter concatenation when generating ORM with inspectdb (#331)
+- Fix KeyError when deleting a field with unqiue=True. (#364)
+- Correct the click import. (#360)
+- Improve CLI help text and output. (#355)
+- Fix mysql drop unique index raises OperationalError. (#346)
+  **Upgrade note:**
+    1. Use column name as unique key name for mysql
+    2. Drop support for Python3.7
+
+## 0.7
+
+### [0.7.2](../../releases/tag/v0.7.2) - 2023-07-20
+
+- Support virtual fields.
+- Fix modify multiple times. (#279)
+- Added `-i` and `--in-transaction` options to `aerich migrate` command. (#296)
+- Fix generates two semicolons in a row. (#301)
+
+### 0.7.1
+
+- Fix syntax error with python3.8.10. (#265)
+- Fix sql generate error. (#263)
+- Fix initialize an empty database. (#267)
+
+### 0.7.1rc1
+
+- Fix postgres sql error (#263)
+
+### 0.7.0
+
+**Now aerich use `.py` file to record versions.**
+
+Upgrade Note:
+
+1. Drop `aerich` table
+2. Delete `migrations/models` folder
+3. Run `aerich init-db`
+
+- Improve `inspectdb` adding support to `postgresql::numeric` data type
+- Add support for dynamically load DDL classes easing to add support to
+  new databases without changing `Migrate` class logic
+- Fix decimal field change. (#246)
+- Support add/remove field with index.
+
+## 0.6
+
+### 0.6.3
+
+- Improve `inspectdb` and support `postgres` & `sqlite`.
+
+### 0.6.2
+
+- Support migration for specified index. (#203)
+
+### 0.6.1
+
+- Fix `pyproject.toml` not existing error. (#217)
+
+### 0.6.0
+
+- Change default config file from `aerich.ini` to `pyproject.toml`. (#197)
+
+  **Upgrade note:**
+    1. Run `aerich init -t config.TORTOISE_ORM`.
+    2. Remove `aerich.ini`.
+- Remove `pydantic` dependency. (#198)
+- `inspectdb` support `DATE`. (#215)
+
+## 0.5
+
+### 0.5.8
+
+- Support `indexes` change. (#193)
+
+### 0.5.7
+
+- Fix no module found error. (#188) (#189)
+
+### 0.5.6
+
+- Add `Command` class. (#148) (#141) (#123) (#106)
+- Fix: migrate doesn't use source_field in unique_together. (#181)
+
+### 0.5.5
+
+- Fix KeyError: 'src_folder' after upgrading aerich to 0.5.4. (#176)
+- Fix MySQL 5.X rename column.
+- Fix `db_constraint` when fk changed. (#179)
+
+### 0.5.4
+
+- Fix incorrect index creation order. (#151)
+- Not catch exception when import config. (#164)
+- Support `drop column` for sqlite. (#40)
+
+### 0.5.3
+
+- Fix postgre alter null. (#142)
+- Fix default function when migrate. (#147)
+
+### 0.5.2
+
+- Fix rename field on the field add. (#134)
+- Fix postgres field type change error. (#135)
+- Fix inspectdb for `FloatField`. (#138)
+- Support `rename table`. (#139)
+
+### 0.5.1
+
+- Fix tortoise connections not being closed properly. (#120)
+- Fix bug for field change. (#119)
+- Fix drop model in the downgrade. (#132)
+
+### 0.5.0
+
+- Refactor core code, now has no limitation for everything.
+
 ## 0.4

 ### 0.4.4
--- a/41
+++ b/41
@@ -8,32 +8,26 @@ POSTGRES_HOST ?= "127.0.0.1"
 POSTGRES_PORT ?= 5432
 POSTGRES_PASS ?= "123456"

-help:
-	@echo "Aerich development makefile"
-	@echo
-	@echo  "usage: make <target>"
-	@echo  "Targets:"
-	@echo  "    up			Updates dev/test dependencies"
-	@echo  "    deps		Ensure dev/test dependencies are installed"
-	@echo  "    check		Checks that build is sane"
-	@echo  "    lint		Reports all linter violations"
-	@echo  "    test		Runs all tests"
-	@echo  "    style		Auto-formats the code"
-
 up:
 	@poetry update

 deps:
-	@poetry install -E dbdrivers
+	@poetry install -E asyncpg -E asyncmy

-style: deps
-	isort -src $(checkfiles)
-	black $(black_opts) $(checkfiles)
+_style:
+	@isort -src $(checkfiles)
+	@black $(black_opts) $(checkfiles)
+style: deps _style

-check: deps
-	black --check $(black_opts) $(checkfiles) || (echo "Please run 'make style' to auto-fix style issues" && false)
-	flake8 $(checkfiles)
-	bandit -x tests -r $(checkfiles)
+_check:
+	@black --check $(black_opts) $(checkfiles) || (echo "Please run 'make style' to auto-fix style issues" && false)
+	@ruff check $(checkfiles)
+	@mypy $(checkfiles)
+ifneq ($(shell python -c 'import sys;is_py38=sys.version_info<(3,9);rc=int(is_py38);sys.exit(rc)'),)
+	# Run bandit with Python3.9+, as the `usedforsecurity=...` parameter of `hashlib.new` is only added from Python 3.9 onwards.
+	@bandit -r aerich
+endif
+check: deps _check

 test: deps
 	$(py_warn) TEST_DB=sqlite://:memory: py.test
@@ -45,11 +39,12 @@ test_mysql:
 	$(py_warn) TEST_DB="mysql://root:$(MYSQL_PASS)@$(MYSQL_HOST):$(MYSQL_PORT)/test_\{\}" pytest -vv -s

 test_postgres:
-	$(py_warn) TEST_DB="postgres://postgres:$(POSTGRES_PASS)@$(POSTGRES_HOST):$(POSTGRES_PORT)/test_\{\}" pytest
+	$(py_warn) TEST_DB="postgres://postgres:$(POSTGRES_PASS)@$(POSTGRES_HOST):$(POSTGRES_PORT)/test_\{\}" pytest -vv -s

-testall: deps test_sqlite test_postgres test_mysql
+_testall: test_sqlite test_postgres test_mysql
+testall: deps _testall

 build: deps
 	@poetry build

-ci: check testall
+ci: check _testall
--- a/README.md
+++ b/README.md
@@ -1,23 +1,23 @@
 # Aerich

 [![image](https://img.shields.io/pypi/v/aerich.svg?style=flat)](https://pypi.python.org/pypi/aerich)
-[![image](https://img.shields.io/github/license/long2ice/aerich)](https://github.com/long2ice/aerich)
-[![image](https://github.com/long2ice/aerich/workflows/pypi/badge.svg)](https://github.com/long2ice/aerich/actions?query=workflow:pypi)
-[![image](https://github.com/long2ice/aerich/workflows/test/badge.svg)](https://github.com/long2ice/aerich/actions?query=workflow:test)
+[![image](https://img.shields.io/github/license/tortoise/aerich)](https://github.com/tortoise/aerich)
+[![image](https://github.com/tortoise/aerich/workflows/pypi/badge.svg)](https://github.com/tortoise/aerich/actions?query=workflow:pypi)
+[![image](https://github.com/tortoise/aerich/workflows/ci/badge.svg)](https://github.com/tortoise/aerich/actions?query=workflow:ci)
+
+English | [Русский](./README_RU.md)

 ## Introduction

-Aerich is a database migrations tool for Tortoise-ORM, which like alembic for SQLAlchemy, or Django ORM with it\'s own
-migrations solution.
-
-**Important: You can only use absolutely import in your `models.py` to make `aerich` work.**
+Aerich is a database migrations tool for TortoiseORM, which is like alembic for SQLAlchemy, or like Django ORM with
+it\'s own migration solution.

 ## Install

 Just install from pypi:

 ```shell
-> pip install aerich
+pip install aerich
 ```

 ## Quick Start
@@ -28,10 +28,9 @@ Just install from pypi:
 Usage: aerich [OPTIONS] COMMAND [ARGS]...

 Options:
-  -c, --config TEXT  Config file.  [default: aerich.ini]
-  --app TEXT         Tortoise-ORM app name.  [default: models]
-  -n, --name TEXT    Name of section in .ini file to use for aerich config.
-                     [default: aerich]
+  -V, --version      Show the version and exit.
+  -c, --config TEXT  Config file.  [default: pyproject.toml]
+  --app TEXT         Tortoise-ORM app name.
  -h, --help         Show this message and exit.

 Commands:
@@ -42,12 +41,12 @@ Commands:
  init-db    Generate schema and generate app migrate location.
  inspectdb  Introspects the database tables to standard output as...
  migrate    Generate migrate changes file.
-  upgrade    Upgrade to latest version.
+  upgrade    Upgrade to specified version.
 ```

 ## Usage

-You need add `aerich.models` to your `Tortoise-ORM` config first, example:
+You need to add `aerich.models` to your `Tortoise-ORM` config first. Example:

 ```python
 TORTOISE_ORM = {
@@ -71,19 +70,20 @@ Usage: aerich init [OPTIONS]
  Init config file and generate root migrate location.

 Options:
-  -t, --tortoise-orm TEXT  Tortoise-ORM config module dict variable, like settings.TORTOISE_ORM.
-                           [required]
+  -t, --tortoise-orm TEXT  Tortoise-ORM config module dict variable, like
+                           settings.TORTOISE_ORM.  [required]
  --location TEXT          Migrate store location.  [default: ./migrations]
+  -s, --src_folder TEXT    Folder of the source, relative to the project root.
  -h, --help               Show this message and exit.
 ```

-Init config file and location:
+Initialize the config file and migrations location:

 ```shell
 > aerich init -t tests.backends.mysql.TORTOISE_ORM

 Success create migrate location ./migrations
-Success generate config file aerich.ini
+Success write config to pyproject.toml
 ```

 ### Init db
@@ -95,29 +95,38 @@ Success create app migrate location ./migrations/models
 Success generate schema for app "models"
 ```

-If your Tortoise-ORM app is not default `models`, you must specify
-`--app` like `aerich --app other_models init-db`.
+If your Tortoise-ORM app is not the default `models`, you must specify the correct app via `--app`,
+e.g. `aerich --app other_models init-db`.

 ### Update models and make migrate

 ```shell
 > aerich migrate --name drop_column

-Success migrate 1_202029051520102929_drop_column.sql
+Success migrate 1_202029051520102929_drop_column.py
 ```

 Format of migrate filename is
-`{version_num}_{datetime}_{name|update}.sql`.
+`{version_num}_{datetime}_{name|update}.py`.

-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.
+If `aerich` guesses you are renaming a column, it will ask `Rename {old_column} to {new_column} [True]`. You can choose
+`True` to rename column without column drop, or choose `False` to drop the column then create. Note that the latter may
+lose data.
+
+If you need to manually write migration, you could generate empty file:
+
+```shell
+> aerich migrate --name add_index --empty
+
+Success migrate 1_202326122220101229_add_index.py
+```

 ### Upgrade to latest version

 ```shell
 > aerich upgrade

-Success upgrade 1_202029051520102929_drop_column.sql
+Success upgrade 1_202029051520102929_drop_column.py
 ```

 Now your db is migrated to latest.
@@ -125,7 +134,7 @@ Now your db is migrated to latest.
 ### Downgrade to specified version

 ```shell
-> aerich init -h
+> aerich downgrade -h

 Usage: aerich downgrade [OPTIONS]

@@ -143,17 +152,17 @@ Options:
 ```shell
 > aerich downgrade

-Success downgrade 1_202029051520102929_drop_column.sql
+Success downgrade 1_202029051520102929_drop_column.py
 ```

-Now your db rollback to specified version.
+Now your db is rolled back to the specified version.

 ### Show history

 ```shell
 > aerich history

-1_202029051520102929_drop_column.sql
+1_202029051520102929_drop_column.py
 ```

 ### Show heads to be migrated
@@ -161,11 +170,13 @@ Now your db rollback to specified version.
 ```shell
 > aerich heads

-1_202029051520102929_drop_column.sql
+1_202029051520102929_drop_column.py
 ```

 ### Inspect db tables to TortoiseORM model

+Currently `inspectdb` support MySQL & Postgres & SQLite.
+
 ```shell
 Usage: aerich inspectdb [OPTIONS]

@@ -179,17 +190,53 @@ Options:
 Inspect all tables and print to console:

 ```shell
-aerich --app models inspectdb -t user 
+aerich --app models inspectdb
 ```

-Inspect a specified table in default app and redirect to `models.py`:
+Inspect a specified table in the default app and redirect to `models.py`:

 ```shell
 aerich inspectdb -t user > models.py
 ```

-Note that this command is restricted, which is not supported in some solutions, such as `IntEnumField`
-and `ForeignKeyField` and so on.
+For example, you table is:
+
+```sql
+CREATE TABLE `test`
+(
+    `id`       int            NOT NULL AUTO_INCREMENT,
+    `decimal`  decimal(10, 2) NOT NULL,
+    `date`     date                                    DEFAULT NULL,
+    `datetime` datetime       NOT NULL                 DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
+    `time`     time                                    DEFAULT NULL,
+    `float`    float                                   DEFAULT NULL,
+    `string`   varchar(200) COLLATE utf8mb4_general_ci DEFAULT NULL,
+    `tinyint`  tinyint                                 DEFAULT NULL,
+    PRIMARY KEY (`id`),
+    KEY `asyncmy_string_index` (`string`)
+) ENGINE = InnoDB
+  DEFAULT CHARSET = utf8mb4
+  COLLATE = utf8mb4_general_ci
+```
+
+Now run `aerich inspectdb -t test` to see the generated model:
+
+```python
+from tortoise import Model, fields
+
+
+class Test(Model):
+    date = fields.DateField(null=True, )
+    datetime = fields.DatetimeField(auto_now=True, )
+    decimal = fields.DecimalField(max_digits=10, decimal_places=2, )
+    float = fields.FloatField(null=True, )
+    id = fields.IntField(pk=True, )
+    string = fields.CharField(max_length=200, null=True, )
+    time = fields.TimeField(null=True, )
+    tinyint = fields.BooleanField(null=True, )
+```
+
+Note that this command is limited and can't infer some fields, such as `IntEnumField`, `ForeignKeyField`, and others.

 ### Multiple databases

@@ -206,13 +253,30 @@ tortoise_orm = {
 }
 ```

-You need only specify `aerich.models` in one app, and must specify `--app` when run `aerich migrate` and so on.
+You only need to specify `aerich.models` in one app, and must specify `--app` when running `aerich migrate` and so on.

-## Support this project
+## Restore `aerich` workflow

-| AliPay                                                                                 | WeChatPay                                                                                 | PayPal                                                           |
-| -------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------- | ---------------------------------------------------------------- |
-| <img width="200" src="https://github.com/long2ice/aerich/raw/dev/images/alipay.jpeg"/> | <img width="200" src="https://github.com/long2ice/aerich/raw/dev/images/wechatpay.jpeg"/> | [PayPal](https://www.paypal.me/long2ice) to my account long2ice. |
+In some cases, such as broken changes from upgrade of `aerich`, you can't run `aerich migrate` or `aerich upgrade`, you
+can make the following steps:
+
+1. drop `aerich` table.
+2. delete `migrations/{app}` directory.
+3. rerun `aerich init-db`.
+
+Note that these actions is safe, also you can do that to reset your migrations if your migration files is too many.
+
+## Use `aerich` in application
+
+You can use `aerich` out of cli by use `Command` class.
+
+```python
+from aerich import Command
+
+command = Command(tortoise_config=config, app='models')
+await command.init()
+await command.migrate('test')
+```

 ## License

--- a/README_RU.md
+++ b/README_RU.md
@@ -0,0 +1,274 @@
+# Aerich
+ 
+[![image](https://img.shields.io/pypi/v/aerich.svg?style=flat)](https://pypi.python.org/pypi/aerich)
+[![image](https://img.shields.io/github/license/tortoise/aerich)](https://github.com/tortoise/aerich)
+[![image](https://github.com/tortoise/aerich/workflows/pypi/badge.svg)](https://github.com/tortoise/aerich/actions?query=workflow:pypi)
+[![image](https://github.com/tortoise/aerich/workflows/ci/badge.svg)](https://github.com/tortoise/aerich/actions?query=workflow:ci)
+ 
+[English](./README.md) | Русский
+
+## Введение
+ 
+Aerich - это инструмент для миграции базы данных для TortoiseORM, который аналогичен Alembic для SQLAlchemy или встроенному решению миграций в Django ORM.
+ 
+## Установка
+ 
+Просто установите из pypi:
+ 
+```shell
+pip install aerich
+```
+ 
+## Быстрый старт
+ 
+```shell
+> aerich -h
+ 
+Usage: aerich [OPTIONS] COMMAND [ARGS]...
+ 
+Options:
+  -V, --version      Show the version and exit.
+  -c, --config TEXT  Config file.  [default: pyproject.toml]
+  --app TEXT         Tortoise-ORM app name.
+  -h, --help         Show this message and exit.
+ 
+Commands:
+  downgrade  Downgrade to specified version.
+  heads      Show current available heads in migrate location.
+  history    List all migrate items.
+  init       Init config file and generate root migrate location.
+  init-db    Generate schema and generate app migrate location.
+  inspectdb  Introspects the database tables to standard output as...
+  migrate    Generate migrate changes file.
+  upgrade    Upgrade to specified version.
+```
+ 
+## Использование
+ 
+Сначала вам нужно добавить aerich.models в конфигурацию вашего Tortoise-ORM. Пример:
+ 
+```python
+TORTOISE_ORM = {
+    "connections": {"default": "mysql://root:123456@127.0.0.1:3306/test"},
+    "apps": {
+        "models": {
+            "models": ["tests.models", "aerich.models"],
+            "default_connection": "default",
+        },
+    },
+}
+```
+ 
+### Инициализация
+ 
+```shell
+> aerich init -h
+ 
+Usage: aerich init [OPTIONS]
+ 
+  Init config file and generate root migrate location.
+ 
+Options:
+  -t, --tortoise-orm TEXT  Tortoise-ORM config module dict variable, like
+                           settings.TORTOISE_ORM.  [required]
+  --location TEXT          Migrate store location.  [default: ./migrations]
+  -s, --src_folder TEXT    Folder of the source, relative to the project root.
+  -h, --help               Show this message and exit.
+```
+ 
+Инициализируйте файл конфигурации и задайте местоположение миграций:
+ 
+```shell
+> aerich init -t tests.backends.mysql.TORTOISE_ORM
+ 
+Success create migrate location ./migrations
+Success write config to pyproject.toml
+```
+ 
+### Инициализация базы данных
+ 
+```shell
+> aerich init-db
+ 
+Success create app migrate location ./migrations/models
+Success generate schema for app "models"
+```
+ 
+Если ваше приложение Tortoise-ORM не является приложением по умолчанию с именем models, вы должны указать правильное имя приложения с помощью параметра --app, например: aerich --app other_models init-db.
+ 
+### Обновление моделей и создание миграции
+ 
+```shell
+> aerich migrate --name drop_column
+ 
+Success migrate 1_202029051520102929_drop_column.py
+```
+ 
+Формат имени файла миграции следующий: `{версия}_{дата_и_время}_{имя|обновление}.py`.
+ 
+Если aerich предполагает, что вы переименовываете столбец, он спросит: 
+Переименовать `{старый_столбец} в {новый_столбец} [True]`. Вы можете выбрать `True`,
+чтобы переименовать столбец без удаления столбца, или выбрать `False`, чтобы удалить столбец,
+а затем создать новый. Обратите внимание, что последний вариант может привести к потере данных.
+ 
+ 
+### Обновление до последней версии
+ 
+```shell
+> aerich upgrade
+ 
+Success upgrade 1_202029051520102929_drop_column.py
+```
+ 
+Теперь ваша база данных обновлена до последней версии.
+ 
+### Откат до указанной версии
+ 
+```shell
+> aerich downgrade -h
+ 
+Usage: aerich downgrade [OPTIONS]
+ 
+  Downgrade to specified version.
+ 
+Options:
+  -v, --version INTEGER  Specified version, default to last.  [default: -1]
+  -d, --delete           Delete version files at the same time.  [default:
+                         False]
+ 
+  --yes                  Confirm the action without prompting.
+  -h, --help             Show this message and exit.
+```
+ 
+```shell
+> aerich downgrade
+ 
+Success downgrade 1_202029051520102929_drop_column.py
+```
+ 
+Теперь ваша база данных откатилась до указанной версии.
+ 
+### Показать историю
+ 
+```shell
+> aerich history
+ 
+1_202029051520102929_drop_column.py
+```
+ 
+### Чтобы узнать, какие миграции должны быть применены, можно использовать команду:
+ 
+```shell
+> aerich heads
+ 
+1_202029051520102929_drop_column.py
+```
+ 
+### Осмотр таблиц базы данных для модели TortoiseORM
+ 
+В настоящее время inspectdb поддерживает MySQL, Postgres и SQLite.
+ 
+```shell
+Usage: aerich inspectdb [OPTIONS]
+ 
+  Introspects the database tables to standard output as TortoiseORM model.
+ 
+Options:
+  -t, --table TEXT  Which tables to inspect.
+  -h, --help        Show this message and exit.
+```
+ 
+Посмотреть все таблицы и вывести их на консоль:
+ 
+```shell
+aerich --app models inspectdb
+```
+ 
+Осмотреть указанную таблицу в приложении по умолчанию и перенаправить в models.py:
+ 
+```shell
+aerich inspectdb -t user > models.py
+```
+ 
+Например, ваша таблица выглядит следующим образом:
+ 
+```sql
+CREATE TABLE `test`
+(
+    `id`       int            NOT NULL AUTO_INCREMENT,
+    `decimal`  decimal(10, 2) NOT NULL,
+    `date`     date                                    DEFAULT NULL,
+    `datetime` datetime       NOT NULL                 DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
+    `time`     time                                    DEFAULT NULL,
+    `float`    float                                   DEFAULT NULL,
+    `string`   varchar(200) COLLATE utf8mb4_general_ci DEFAULT NULL,
+    `tinyint`  tinyint                                 DEFAULT NULL,
+    PRIMARY KEY (`id`),
+    KEY `asyncmy_string_index` (`string`)
+) ENGINE = InnoDB
+  DEFAULT CHARSET = utf8mb4
+  COLLATE = utf8mb4_general_ci
+```
+ 
+Теперь выполните команду aerich inspectdb -t test, чтобы увидеть сгенерированную модель:
+ 
+```python
+from tortoise import Model, fields
+ 
+ 
+class Test(Model):
+    date = fields.DateField(null=True, )
+    datetime = fields.DatetimeField(auto_now=True, )
+    decimal = fields.DecimalField(max_digits=10, decimal_places=2, )
+    float = fields.FloatField(null=True, )
+    id = fields.IntField(pk=True, )
+    string = fields.CharField(max_length=200, null=True, )
+    time = fields.TimeField(null=True, )
+    tinyint = fields.BooleanField(null=True, )
+```
+ 
+Обратите внимание, что эта команда имеет ограничения и не может автоматически определить некоторые поля, такие как `IntEnumField`, `ForeignKeyField` и другие.
+ 
+### Несколько баз данных
+ 
+```python
+tortoise_orm = {
+    "connections": {
+        "default": expand_db_url(db_url, True),
+        "second": expand_db_url(db_url_second, True),
+    },
+    "apps": {
+        "models": {"models": ["tests.models", "aerich.models"], "default_connection": "default"},
+        "models_second": {"models": ["tests.models_second"], "default_connection": "second", },
+    },
+}
+```
+ 
+Вам нужно указать `aerich.models` только в одном приложении и должны указывать `--app` при запуске команды `aerich migrate` и т.д.
+ 
+## Восстановление рабочего процесса aerich
+ 
+В некоторых случаях, например, при возникновении проблем после обновления `aerich`, вы не можете запустить `aerich migrate` или `aerich upgrade`. В таком случае вы можете выполнить следующие шаги:
+ 
+1. удалите таблицы `aerich`.
+2. удалите директорию `migrations/{app}`.
+3. rerun `aerich init-db`.
+ 
+Обратите внимание, что эти действия безопасны, и вы можете использовать их для сброса миграций, если у вас слишком много файлов миграции.
+ 
+## Использование aerich в приложении
+ 
+Вы можете использовать `aerich` вне командной строки, используя класс `Command`.
+ 
+```python
+from aerich import Command
+ 
+command = Command(tortoise_config=config, app='models')
+await command.init()
+await command.migrate('test')
+```
+ 
+## Лицензия
+ 
+Этот проект лицензирован в соответствии с лицензией
+[Apache-2.0](https://github.com/long2ice/aerich/blob/master/LICENSE) Лицензия.
--- a/aerich/init.py
+++ b/aerich/init.py
@@ -1 +1,153 @@
-__version__ = "0.4.4"
+import os
+from pathlib import Path
+from typing import TYPE_CHECKING, List, Optional, Type
+
+from tortoise import Tortoise, generate_schema_for_client
+from tortoise.exceptions import OperationalError
+from tortoise.transactions import in_transaction
+from tortoise.utils import get_schema_sql
+
+from aerich.exceptions import DowngradeError
+from aerich.inspectdb.mysql import InspectMySQL
+from aerich.inspectdb.postgres import InspectPostgres
+from aerich.inspectdb.sqlite import InspectSQLite
+from aerich.migrate import MIGRATE_TEMPLATE, Migrate
+from aerich.models import Aerich
+from aerich.utils import (
+    get_app_connection,
+    get_app_connection_name,
+    get_models_describe,
+    import_py_file,
+)
+
+if TYPE_CHECKING:
+    from aerich.inspectdb import Inspect  # noqa:F401
+
+
+class Command:
+    def __init__(
+        self,
+        tortoise_config: dict,
+        app: str = "models",
+        location: str = "./migrations",
+    ) -> None:
+        self.tortoise_config = tortoise_config
+        self.app = app
+        self.location = location
+        Migrate.app = app
+
+    async def init(self) -> None:
+        await Migrate.init(self.tortoise_config, self.app, self.location)
+
+    async def _upgrade(self, conn, version_file) -> None:
+        file_path = Path(Migrate.migrate_location, version_file)
+        m = import_py_file(file_path)
+        upgrade = getattr(m, "upgrade")
+        await conn.execute_script(await upgrade(conn))
+        await Aerich.create(
+            version=version_file,
+            app=self.app,
+            content=get_models_describe(self.app),
+        )
+
+    async def upgrade(self, run_in_transaction: bool = True) -> List[str]:
+        migrated = []
+        for version_file in Migrate.get_all_version_files():
+            try:
+                exists = await Aerich.exists(version=version_file, app=self.app)
+            except OperationalError:
+                exists = False
+            if not exists:
+                app_conn_name = get_app_connection_name(self.tortoise_config, self.app)
+                if run_in_transaction:
+                    async with in_transaction(app_conn_name) as conn:
+                        await self._upgrade(conn, version_file)
+                else:
+                    app_conn = get_app_connection(self.tortoise_config, self.app)
+                    await self._upgrade(app_conn, version_file)
+                migrated.append(version_file)
+        return migrated
+
+    async def downgrade(self, version: int, delete: bool) -> List[str]:
+        ret: List[str] = []
+        if version == -1:
+            specified_version = await Migrate.get_last_version()
+        else:
+            specified_version = await Aerich.filter(
+                app=self.app, version__startswith=f"{version}_"
+            ).first()
+        if not specified_version:
+            raise DowngradeError("No specified version found")
+        if version == -1:
+            versions = [specified_version]
+        else:
+            versions = await Aerich.filter(app=self.app, pk__gte=specified_version.pk)
+        for version_obj in versions:
+            file = version_obj.version
+            async with in_transaction(
+                get_app_connection_name(self.tortoise_config, self.app)
+            ) as conn:
+                file_path = Path(Migrate.migrate_location, file)
+                m = import_py_file(file_path)
+                downgrade = getattr(m, "downgrade")
+                downgrade_sql = await downgrade(conn)
+                if not downgrade_sql.strip():
+                    raise DowngradeError("No downgrade items found")
+                await conn.execute_script(downgrade_sql)
+                await version_obj.delete()
+                if delete:
+                    os.unlink(file_path)
+                ret.append(file)
+        return ret
+
+    async def heads(self) -> List[str]:
+        ret = []
+        versions = Migrate.get_all_version_files()
+        for version in versions:
+            if not await Aerich.exists(version=version, app=self.app):
+                ret.append(version)
+        return ret
+
+    async def history(self) -> List[str]:
+        versions = Migrate.get_all_version_files()
+        return [version for version in versions]
+
+    async def inspectdb(self, tables: Optional[List[str]] = None) -> str:
+        connection = get_app_connection(self.tortoise_config, self.app)
+        dialect = connection.schema_generator.DIALECT
+        if dialect == "mysql":
+            cls: Type["Inspect"] = InspectMySQL
+        elif dialect == "postgres":
+            cls = InspectPostgres
+        elif dialect == "sqlite":
+            cls = InspectSQLite
+        else:
+            raise NotImplementedError(f"{dialect} is not supported")
+        inspect = cls(connection, tables)
+        return await inspect.inspect()
+
+    async def migrate(self, name: str = "update", empty: bool = False) -> str:
+        return await Migrate.migrate(name, empty)
+
+    async def init_db(self, safe: bool) -> None:
+        location = self.location
+        app = self.app
+        dirname = Path(location, app)
+        dirname.mkdir(parents=True)
+
+        await Tortoise.init(config=self.tortoise_config)
+        connection = get_app_connection(self.tortoise_config, app)
+        await generate_schema_for_client(connection, safe)
+
+        schema = get_schema_sql(connection, safe)
+
+        version = await Migrate.generate_version()
+        await Aerich.create(
+            version=version,
+            app=app,
+            content=get_models_describe(app),
+        )
+        version_file = Path(dirname, version)
+        content = MIGRATE_TEMPLATE.format(upgrade_sql=schema, downgrade_sql="")
+        with open(version_file, "w", encoding="utf-8") as f:
+            f.write(content)
--- a/aerich/cli.py
+++ b/aerich/cli.py
@@ -1,46 +1,21 @@
-import asyncio
 import os
-import sys
-from configparser import ConfigParser
-from functools import wraps
 from pathlib import Path
-from typing import List
+from typing import Dict, List, cast

-import click
-from click import Context, UsageError
-from tortoise import Tortoise, generate_schema_for_client
-from tortoise.exceptions import OperationalError
-from tortoise.transactions import in_transaction
-from tortoise.utils import get_schema_sql
+import asyncclick as click
+import tomlkit
+from asyncclick import Context, UsageError
+from tomlkit.exceptions import NonExistentKey

-from aerich.inspectdb import InspectDb
-from aerich.migrate import Migrate
-from aerich.utils import (
-    get_app_connection,
-    get_app_connection_name,
-    get_tortoise_config,
-    get_version_content_from_file,
-    write_version_file,
-)
+from aerich import Command
+from aerich.enums import Color
+from aerich.exceptions import DowngradeError
+from aerich.utils import add_src_path, get_tortoise_config
+from aerich.version import __version__

-from . import __version__
-from .enums import Color
-from .models import Aerich
-
-parser = ConfigParser()
-
-
-def coro(f):
-    @wraps(f)
-    def wrapper(*args, **kwargs):
-        loop = asyncio.get_event_loop()
-        ctx = args[0]
-        loop.run_until_complete(f(*args, **kwargs))
-        app = ctx.obj.get("app")
-        if app:
-            Migrate.remove_old_model_file(app, ctx.obj["location"])
-
-    return wrapper
+CONFIG_DEFAULT_VALUES = {
+    "src_folder": ".",
+}


@click.group(context_settings={"help_option_names": ["-h", "--help"]})
@@ -48,86 +23,76 @@ def coro(f):
@click.option(
    "-c",
    "--config",
-    default="aerich.ini",
+    default="pyproject.toml",
    show_default=True,
    help="Config file.",
 )
@click.option("--app", required=False, help="Tortoise-ORM app name.")
-@click.option(
-    "-n",
-    "--name",
-    default="aerich",
-    show_default=True,
-    help="Name of section in .ini file to use for aerich config.",
-)
@click.pass_context
-@coro
-async def cli(ctx: Context, config, app, name):
+async def cli(ctx: Context, config, app) -> None:
    ctx.ensure_object(dict)
    ctx.obj["config_file"] = config
-    ctx.obj["name"] = name

    invoked_subcommand = ctx.invoked_subcommand
    if invoked_subcommand != "init":
-        if not Path(config).exists():
-            raise UsageError("You must exec init first", ctx=ctx)
-        parser.read(config)
-
-        location = parser[name]["location"]
-        tortoise_orm = parser[name]["tortoise_orm"]
-
+        config_path = Path(config)
+        if not config_path.exists():
+            raise UsageError(
+                "You need to run `aerich init` first to create the config file.", ctx=ctx
+            )
+        content = config_path.read_text()
+        doc: dict = tomlkit.parse(content)
+        try:
+            tool = cast(Dict[str, str], doc["tool"]["aerich"])
+            location = tool["location"]
+            tortoise_orm = tool["tortoise_orm"]
+            src_folder = tool.get("src_folder", CONFIG_DEFAULT_VALUES["src_folder"])
+        except NonExistentKey:
+            raise UsageError("You need run `aerich init` again when upgrading to aerich 0.6.0+.")
+        add_src_path(src_folder)
        tortoise_config = get_tortoise_config(ctx, tortoise_orm)
-        app = app or list(tortoise_config.get("apps").keys())[0]
-        ctx.obj["config"] = tortoise_config
-        ctx.obj["location"] = location
-        ctx.obj["app"] = app
-        Migrate.app = app
+        if not app:
+            apps_config = cast(dict, tortoise_config.get("apps"))
+            app = list(apps_config.keys())[0]
+        command = Command(tortoise_config=tortoise_config, app=app, location=location)
+        ctx.obj["command"] = command
        if invoked_subcommand != "init-db":
            if not Path(location, app).exists():
-                raise UsageError("You must exec init-db first", ctx=ctx)
-            await Migrate.init_with_old_models(tortoise_config, app, location)
+                raise UsageError(
+                    "You need to run `aerich init-db` first to initialize the database.", ctx=ctx
+                )
+            await command.init()


-@cli.command(help="Generate migrate changes file.")
-@click.option("--name", default="update", show_default=True, help="Migrate name.")
+@cli.command(help="Generate a migration file for the current state of the models.")
+@click.option("--name", default="update", show_default=True, help="Migration name.")
+@click.option("--empty", default=False, is_flag=True, help="Generate an empty migration file.")
@click.pass_context
-@coro
-async def migrate(ctx: Context, name):
-    ret = await Migrate.migrate(name)
+async def migrate(ctx: Context, name, empty) -> None:
+    command = ctx.obj["command"]
+    ret = await command.migrate(name, empty)
    if not ret:
        return click.secho("No changes detected", fg=Color.yellow)
-    click.secho(f"Success migrate {ret}", fg=Color.green)
+    click.secho(f"Success creating migration file {ret}", fg=Color.green)


-@cli.command(help="Upgrade to specified version.")
+@cli.command(help="Upgrade to specified migration version.")
+@click.option(
+    "--in-transaction",
+    "-i",
+    default=True,
+    type=bool,
+    help="Make migrations in a single transaction or not. Can be helpful for large migrations or creating concurrent indexes.",
+)
@click.pass_context
-@coro
-async def upgrade(ctx: Context):
-    config = ctx.obj["config"]
-    app = ctx.obj["app"]
-    location = ctx.obj["location"]
-    migrated = False
-    for version_file in Migrate.get_all_version_files():
-        try:
-            exists = await Aerich.exists(version=version_file, app=app)
-        except OperationalError:
-            exists = False
-        if not exists:
-            async with in_transaction(get_app_connection_name(config, app)) as conn:
-                file_path = Path(Migrate.migrate_location, version_file)
-                content = get_version_content_from_file(file_path)
-                upgrade_query_list = content.get("upgrade")
-                for upgrade_query in upgrade_query_list:
-                    await conn.execute_script(upgrade_query)
-                await Aerich.create(
-                    version=version_file,
-                    app=app,
-                    content=Migrate.get_models_content(config, app, location),
-                )
-            click.secho(f"Success upgrade {version_file}", fg=Color.green)
-            migrated = True
+async def upgrade(ctx: Context, in_transaction: bool) -> None:
+    command = ctx.obj["command"]
+    migrated = await command.upgrade(run_in_transaction=in_transaction)
    if not migrated:
        click.secho("No upgrade items found", fg=Color.yellow)
+    else:
+        for version_file in migrated:
+            click.secho(f"Success upgrading to {version_file}", fg=Color.green)


@cli.command(help="Downgrade to specified version.")
@@ -136,8 +101,8 @@ async def upgrade(ctx: Context):
    "--version",
    default=-1,
    type=int,
-    show_default=True,
-    help="Specified version, default to last.",
+    show_default=False,
+    help="Specified version, default to last migration.",
 )
@click.option(
    "-d",
@@ -145,151 +110,123 @@ async def upgrade(ctx: Context):
    is_flag=True,
    default=False,
    show_default=True,
-    help="Delete version files at the same time.",
+    help="Also delete the migration files.",
 )
@click.pass_context
@click.confirmation_option(
-    prompt="Downgrade is dangerous, which maybe lose your data, are you sure?",
+    prompt="Downgrade is dangerous: you might lose your data! Are you sure?",
 )
-@coro
-async def downgrade(ctx: Context, version: int, delete: bool):
-    app = ctx.obj["app"]
-    config = ctx.obj["config"]
-    if version == -1:
-        specified_version = await Migrate.get_last_version()
-    else:
-        specified_version = await Aerich.filter(app=app, version__startswith=f"{version}_").first()
-    if not specified_version:
-        return click.secho("No specified version found", fg=Color.yellow)
-    if version == -1:
-        versions = [specified_version]
-    else:
-        versions = await Aerich.filter(app=app, pk__gte=specified_version.pk)
-    for version in versions:
-        file = version.version
-        async with in_transaction(get_app_connection_name(config, app)) as conn:
-            file_path = Path(Migrate.migrate_location, file)
-            content = get_version_content_from_file(file_path)
-            downgrade_query_list = content.get("downgrade")
-            if not downgrade_query_list:
-                click.secho("No downgrade items found", fg=Color.yellow)
-                return
-            for downgrade_query in downgrade_query_list:
-                await conn.execute_query(downgrade_query)
-            await version.delete()
-            if delete:
-                os.unlink(file_path)
-            click.secho(f"Success downgrade {file}", fg=Color.green)
+async def downgrade(ctx: Context, version: int, delete: bool) -> None:
+    command = ctx.obj["command"]
+    try:
+        files = await command.downgrade(version, delete)
+    except DowngradeError as e:
+        return click.secho(str(e), fg=Color.yellow)
+    for file in files:
+        click.secho(f"Success downgrading to {file}", fg=Color.green)


-@cli.command(help="Show current available heads in migrate location.")
+@cli.command(help="Show currently available heads (unapplied migrations).")
@click.pass_context
-@coro
-async def heads(ctx: Context):
-    app = ctx.obj["app"]
-    versions = Migrate.get_all_version_files()
-    is_heads = False
-    for version in versions:
-        if not await Aerich.exists(version=version, app=app):
-            click.secho(version, fg=Color.green)
-            is_heads = True
-    if not is_heads:
-        click.secho("No available heads,try migrate first", fg=Color.green)
+async def heads(ctx: Context) -> None:
+    command = ctx.obj["command"]
+    head_list = await command.heads()
+    if not head_list:
+        return click.secho("No available heads.", fg=Color.green)
+    for version in head_list:
+        click.secho(version, fg=Color.green)


-@cli.command(help="List all migrate items.")
+@cli.command(help="List all migrations.")
@click.pass_context
-@coro
-async def history(ctx: Context):
-    versions = Migrate.get_all_version_files()
+async def history(ctx: Context) -> None:
+    command = ctx.obj["command"]
+    versions = await command.history()
+    if not versions:
+        return click.secho("No migrations created yet.", fg=Color.green)
    for version in versions:
        click.secho(version, fg=Color.green)
-    if not versions:
-        click.secho("No history,try migrate", fg=Color.green)


-@cli.command(help="Init config file and generate root migrate location.")
+@cli.command(help="Initialize aerich config and create migrations folder.")
@click.option(
    "-t",
    "--tortoise-orm",
    required=True,
-    help="Tortoise-ORM config module dict variable, like settings.TORTOISE_ORM.",
+    help="Tortoise-ORM config dict location, like `settings.TORTOISE_ORM`.",
 )
@click.option(
    "--location",
    default="./migrations",
    show_default=True,
-    help="Migrate store location.",
+    help="Migrations folder.",
+)
+@click.option(
+    "-s",
+    "--src_folder",
+    default=CONFIG_DEFAULT_VALUES["src_folder"],
+    show_default=False,
+    help="Folder of the source, relative to the project root.",
 )
@click.pass_context
-@coro
-async def init(
-    ctx: Context,
-    tortoise_orm,
-    location,
-):
+async def init(ctx: Context, tortoise_orm, location, src_folder) -> None:
    config_file = ctx.obj["config_file"]
-    name = ctx.obj["name"]
-    if Path(config_file).exists():
-        return click.secho("You have inited", fg=Color.yellow)

-    parser.add_section(name)
-    parser.set(name, "tortoise_orm", tortoise_orm)
-    parser.set(name, "location", location)
+    if os.path.isabs(src_folder):
+        src_folder = os.path.relpath(os.getcwd(), src_folder)
+    # Add ./ so it's clear that this is relative path
+    if not src_folder.startswith("./"):
+        src_folder = "./" + src_folder

-    with open(config_file, "w", encoding="utf-8") as f:
-        parser.write(f)
+    # check that we can find the configuration, if not we can fail before the config file gets created
+    add_src_path(src_folder)
+    get_tortoise_config(ctx, tortoise_orm)
+    config_path = Path(config_file)
+    if config_path.exists():
+        content = config_path.read_text()
+    else:
+        content = "[tool.aerich]"
+    doc: dict = tomlkit.parse(content)
+    table = tomlkit.table()
+    table["tortoise_orm"] = tortoise_orm
+    table["location"] = location
+    table["src_folder"] = src_folder
+    doc["tool"]["aerich"] = table
+
+    config_path.write_text(tomlkit.dumps(doc))

    Path(location).mkdir(parents=True, exist_ok=True)

-    click.secho(f"Success create migrate location {location}", fg=Color.green)
-    click.secho(f"Success generate config file {config_file}", fg=Color.green)
+    click.secho(f"Success creating migrations folder {location}", fg=Color.green)
+    click.secho(f"Success writing aerich config to {config_file}", fg=Color.green)


-@cli.command(help="Generate schema and generate app migrate location.")
+@cli.command(help="Generate schema and generate app migration folder.")
@click.option(
+    "-s",
    "--safe",
    type=bool,
+    is_flag=True,
    default=True,
-    help="When set to true, creates the table only when it does not already exist.",
+    help="Create tables only when they do not already exist.",
    show_default=True,
 )
@click.pass_context
-@coro
-async def init_db(ctx: Context, safe):
-    config = ctx.obj["config"]
-    location = ctx.obj["location"]
-    app = ctx.obj["app"]
-
-    dirname = Path(location, app)
+async def init_db(ctx: Context, safe: bool) -> None:
+    command = ctx.obj["command"]
+    app = command.app
+    dirname = Path(command.location, app)
    try:
-        dirname.mkdir(parents=True)
-        click.secho(f"Success create app migrate location {dirname}", fg=Color.green)
+        await command.init_db(safe)
+        click.secho(f"Success creating app migration folder {dirname}", fg=Color.green)
+        click.secho(f'Success generating initial migration file for app "{app}"', fg=Color.green)
    except FileExistsError:
        return click.secho(
-            f"Inited {app} already, or delete {dirname} and try again.", fg=Color.yellow
+            f"App {app} is already initialized. Delete {dirname} and try again.", fg=Color.yellow
        )

-    await Tortoise.init(config=config)
-    connection = get_app_connection(config, app)
-    await generate_schema_for_client(connection, safe)

-    schema = get_schema_sql(connection, safe)
-
-    version = await Migrate.generate_version()
-    await Aerich.create(
-        version=version,
-        app=app,
-        content=Migrate.get_models_content(config, app, location),
-    )
-    content = {
-        "upgrade": [schema],
-    }
-    write_version_file(Path(dirname, version), content)
-    click.secho(f'Success generate schema for app "{app}"', fg=Color.green)
-
-
-@cli.command(help="Introspects the database tables to standard output as TortoiseORM model.")
+@cli.command(help="Prints the current database tables to stdout as Tortoise-ORM models.")
@click.option(
    "-t",
    "--table",
@@ -298,18 +235,13 @@ async def init_db(ctx: Context, safe):
    required=False,
 )
@click.pass_context
-@coro
-async def inspectdb(ctx: Context, table: List[str]):
-    config = ctx.obj["config"]
-    app = ctx.obj["app"]
-    connection = get_app_connection(config, app)
-
-    inspect = InspectDb(connection, table)
-    await inspect.inspect()
+async def inspectdb(ctx: Context, table: List[str]) -> None:
+    command = ctx.obj["command"]
+    ret = await command.inspectdb(table)
+    click.secho(ret)


-def main():
-    sys.path.insert(0, ".")
+def main() -> None:
    cli()


--- a/aerich/coder.py
+++ b/aerich/coder.py
@@ -0,0 +1,32 @@
+import base64
+import json
+import pickle  # nosec: B301,B403
+from typing import Any, Union
+
+from tortoise.indexes import Index
+
+
+class JsonEncoder(json.JSONEncoder):
+    def default(self, obj) -> Any:
+        if isinstance(obj, Index):
+            return {
+                "type": "index",
+                "val": base64.b64encode(pickle.dumps(obj)).decode(),  # nosec: B301
+            }
+        else:
+            return super().default(obj)
+
+
+def object_hook(obj) -> Any:
+    _type = obj.get("type")
+    if not _type:
+        return obj
+    return pickle.loads(base64.b64decode(obj["val"]))  # nosec: B301
+
+
+def encoder(obj: dict) -> str:
+    return json.dumps(obj, cls=JsonEncoder)
+
+
+def decoder(obj: Union[str, bytes]) -> Any:
+    return json.loads(obj, object_hook=object_hook)
--- a/aerich/ddl/init.py
+++ b/aerich/ddl/init.py
@@ -1,8 +1,10 @@
-from typing import List, Type
+from enum import Enum
+from typing import Any, List, Type, cast

-from tortoise import BaseDBAsyncClient, ForeignKeyFieldInstance, ManyToManyFieldInstance, Model
+from tortoise import BaseDBAsyncClient, Model
 from tortoise.backends.base.schema_generator import BaseSchemaGenerator
-from tortoise.fields import CASCADE, Field, JSONField, TextField, UUIDField
+
+from aerich.utils import is_default_function


 class BaseDDL:
@@ -11,65 +13,86 @@ class BaseDDL:
    _DROP_TABLE_TEMPLATE = 'DROP TABLE IF EXISTS "{table_name}"'
    _ADD_COLUMN_TEMPLATE = 'ALTER TABLE "{table_name}" ADD {column}'
    _DROP_COLUMN_TEMPLATE = 'ALTER TABLE "{table_name}" DROP COLUMN "{column_name}"'
+    _ALTER_DEFAULT_TEMPLATE = 'ALTER TABLE "{table_name}" ALTER COLUMN "{column}" {default}'
    _RENAME_COLUMN_TEMPLATE = (
        'ALTER TABLE "{table_name}" RENAME COLUMN "{old_column_name}" TO "{new_column_name}"'
    )
    _ADD_INDEX_TEMPLATE = (
-        'ALTER TABLE "{table_name}" ADD {unique} INDEX "{index_name}" ({column_names})'
+        'ALTER TABLE "{table_name}" ADD {unique}INDEX "{index_name}" ({column_names})'
    )
    _DROP_INDEX_TEMPLATE = 'ALTER TABLE "{table_name}" DROP INDEX "{index_name}"'
    _ADD_FK_TEMPLATE = 'ALTER TABLE "{table_name}" ADD CONSTRAINT "{fk_name}" FOREIGN KEY ("{db_column}") REFERENCES "{table}" ("{field}") ON DELETE {on_delete}'
    _DROP_FK_TEMPLATE = 'ALTER TABLE "{table_name}" DROP FOREIGN KEY "{fk_name}"'
-    _M2M_TABLE_TEMPLATE = 'CREATE TABLE "{table_name}" ("{backward_key}" {backward_type} NOT NULL REFERENCES "{backward_table}" ("{backward_field}") ON DELETE CASCADE,"{forward_key}" {forward_type} NOT NULL REFERENCES "{forward_table}" ("{forward_field}") ON DELETE {on_delete}){extra}{comment};'
+    _M2M_TABLE_TEMPLATE = (
+        'CREATE TABLE "{table_name}" (\n'
+        '    "{backward_key}" {backward_type} NOT NULL REFERENCES "{backward_table}" ("{backward_field}") ON DELETE CASCADE,\n'
+        '    "{forward_key}" {forward_type} NOT NULL REFERENCES "{forward_table}" ("{forward_field}") ON DELETE {on_delete}\n'
+        "){extra}{comment}"
+    )
    _MODIFY_COLUMN_TEMPLATE = 'ALTER TABLE "{table_name}" MODIFY COLUMN {column}'
    _CHANGE_COLUMN_TEMPLATE = (
        'ALTER TABLE "{table_name}" CHANGE {old_column_name} {new_column_name} {new_column_type}'
    )
+    _RENAME_TABLE_TEMPLATE = 'ALTER TABLE "{old_table_name}" RENAME TO "{new_table_name}"'

-    def __init__(self, client: "BaseDBAsyncClient"):
+    def __init__(self, client: "BaseDBAsyncClient") -> None:
        self.client = client
        self.schema_generator = self.schema_generator_cls(client)

-    def create_table(self, model: "Type[Model]"):
-        return self.schema_generator._get_table_sql(model, True)["table_creation_string"]
-
-    def drop_table(self, model: "Type[Model]"):
-        return self._DROP_TABLE_TEMPLATE.format(table_name=model._meta.db_table)
-
-    def create_m2m_table(self, model: "Type[Model]", field: ManyToManyFieldInstance):
-        return self._M2M_TABLE_TEMPLATE.format(
-            table_name=field.through,
-            backward_table=model._meta.db_table,
-            forward_table=field.related_model._meta.db_table,
-            backward_field=model._meta.db_pk_column,
-            forward_field=field.related_model._meta.db_pk_column,
-            backward_key=field.backward_key,
-            backward_type=model._meta.pk.get_for_dialect(self.DIALECT, "SQL_TYPE"),
-            forward_key=field.forward_key,
-            forward_type=field.related_model._meta.pk.get_for_dialect(self.DIALECT, "SQL_TYPE"),
-            on_delete=CASCADE,
-            extra=self.schema_generator._table_generate_extra(table=field.through),
-            comment=self.schema_generator._table_comment_generator(
-                table=field.through, comment=field.description
-            )
-            if field.description
-            else "",
+    def create_table(self, model: "Type[Model]") -> str:
+        return self.schema_generator._get_table_sql(model, True)["table_creation_string"].rstrip(
+            ";"
        )

-    def drop_m2m(self, field: ManyToManyFieldInstance):
-        return self._DROP_TABLE_TEMPLATE.format(table_name=field.through)
+    def drop_table(self, table_name: str) -> str:
+        return self._DROP_TABLE_TEMPLATE.format(table_name=table_name)

-    def _get_default(self, model: "Type[Model]", field_object: Field):
+    def create_m2m(
+        self, model: "Type[Model]", field_describe: dict, reference_table_describe: dict
+    ) -> str:
+        through = cast(str, field_describe.get("through"))
+        description = field_describe.get("description")
+        pk_field = cast(dict, reference_table_describe.get("pk_field"))
+        reference_id = pk_field.get("db_column")
+        db_field_types = cast(dict, pk_field.get("db_field_types"))
+        return self._M2M_TABLE_TEMPLATE.format(
+            table_name=through,
+            backward_table=model._meta.db_table,
+            forward_table=reference_table_describe.get("table"),
+            backward_field=model._meta.db_pk_column,
+            forward_field=reference_id,
+            backward_key=field_describe.get("backward_key"),
+            backward_type=model._meta.pk.get_for_dialect(self.DIALECT, "SQL_TYPE"),
+            forward_key=field_describe.get("forward_key"),
+            forward_type=db_field_types.get(self.DIALECT) or db_field_types.get(""),
+            on_delete=field_describe.get("on_delete"),
+            extra=self.schema_generator._table_generate_extra(table=through),
+            comment=(
+                self.schema_generator._table_comment_generator(table=through, comment=description)
+                if description
+                else ""
+            ),
+        )
+
+    def drop_m2m(self, table_name: str) -> str:
+        return self._DROP_TABLE_TEMPLATE.format(table_name=table_name)
+
+    def _get_default(self, model: "Type[Model]", field_describe: dict) -> Any:
        db_table = model._meta.db_table
-        default = field_object.default
-        db_column = field_object.model_field_name
-        auto_now_add = getattr(field_object, "auto_now_add", False)
-        auto_now = getattr(field_object, "auto_now", False)
+        default = field_describe.get("default")
+        if isinstance(default, Enum):
+            default = default.value
+        db_column = cast(str, field_describe.get("db_column"))
+        auto_now_add = field_describe.get("auto_now_add", False)
+        auto_now = field_describe.get("auto_now", False)
        if default is not None or auto_now_add:
-            if callable(default) or isinstance(field_object, (UUIDField, TextField, JSONField)):
+            if field_describe.get("field_type") in [
+                "UUIDField",
+                "TextField",
+                "JSONField",
+            ] or is_default_function(default):
                default = ""
            else:
-                default = field_object.to_db_value(default, model)
                try:
                    default = self.schema_generator._column_default_generator(
                        db_table,
@@ -81,58 +104,58 @@ class BaseDDL:
                except NotImplementedError:
                    default = ""
        else:
-            default = ""
+            default = None
        return default

-    def add_column(self, model: "Type[Model]", field_object: Field):
-        db_table = model._meta.db_table
+    def add_column(self, model: "Type[Model]", field_describe: dict, is_pk: bool = False) -> str:
+        return self._add_or_modify_column(model, field_describe, is_pk)

-        return self._ADD_COLUMN_TEMPLATE.format(
+    def _add_or_modify_column(self, model, field_describe: dict, is_pk: bool, modify=False) -> str:
+        db_table = model._meta.db_table
+        description = field_describe.get("description")
+        db_column = cast(str, field_describe.get("db_column"))
+        db_field_types = cast(dict, field_describe.get("db_field_types"))
+        default = self._get_default(model, field_describe)
+        if default is None:
+            default = ""
+        if modify:
+            unique = ""
+            template = self._MODIFY_COLUMN_TEMPLATE
+        else:
+            unique = "UNIQUE" if field_describe.get("unique") else ""
+            template = self._ADD_COLUMN_TEMPLATE
+        return template.format(
            table_name=db_table,
            column=self.schema_generator._create_string(
-                db_column=field_object.model_field_name,
-                field_type=field_object.get_for_dialect(self.DIALECT, "SQL_TYPE"),
-                nullable="NOT NULL" if not field_object.null else "",
-                unique="UNIQUE" if field_object.unique else "",
-                comment=self.schema_generator._column_comment_generator(
-                    table=db_table,
-                    column=field_object.model_field_name,
-                    comment=field_object.description,
-                )
-                if field_object.description
-                else "",
-                is_primary_key=field_object.pk,
-                default=self._get_default(model, field_object),
+                db_column=db_column,
+                field_type=db_field_types.get(self.DIALECT, db_field_types.get("")),
+                nullable="NOT NULL" if not field_describe.get("nullable") else "",
+                unique=unique,
+                comment=(
+                    self.schema_generator._column_comment_generator(
+                        table=db_table,
+                        column=db_column,
+                        comment=description,
+                    )
+                    if description
+                    else ""
+                ),
+                is_primary_key=is_pk,
+                default=default,
            ),
        )

-    def drop_column(self, model: "Type[Model]", column_name: str):
+    def drop_column(self, model: "Type[Model]", column_name: str) -> str:
        return self._DROP_COLUMN_TEMPLATE.format(
            table_name=model._meta.db_table, column_name=column_name
        )

-    def modify_column(self, model: "Type[Model]", field_object: Field):
-        db_table = model._meta.db_table
-        return self._MODIFY_COLUMN_TEMPLATE.format(
-            table_name=db_table,
-            column=self.schema_generator._create_string(
-                db_column=field_object.model_field_name,
-                field_type=field_object.get_for_dialect(self.DIALECT, "SQL_TYPE"),
-                nullable="NOT NULL" if not field_object.null else "",
-                unique="",
-                comment=self.schema_generator._column_comment_generator(
-                    table=db_table,
-                    column=field_object.model_field_name,
-                    comment=field_object.description,
-                )
-                if field_object.description
-                else "",
-                is_primary_key=field_object.pk,
-                default=self._get_default(model, field_object),
-            ),
-        )
+    def modify_column(self, model: "Type[Model]", field_describe: dict, is_pk: bool = False) -> str:
+        return self._add_or_modify_column(model, field_describe, is_pk, modify=True)

-    def rename_column(self, model: "Type[Model]", old_column_name: str, new_column_name: str):
+    def rename_column(
+        self, model: "Type[Model]", old_column_name: str, new_column_name: str
+    ) -> str:
        return self._RENAME_COLUMN_TEMPLATE.format(
            table_name=model._meta.db_table,
            old_column_name=old_column_name,
@@ -141,7 +164,7 @@ class BaseDDL:

    def change_column(
        self, model: "Type[Model]", old_column_name: str, new_column_name: str, new_column_type: str
-    ):
+    ) -> str:
        return self._CHANGE_COLUMN_TEMPLATE.format(
            table_name=model._meta.db_table,
            old_column_name=old_column_name,
@@ -149,17 +172,17 @@ class BaseDDL:
            new_column_type=new_column_type,
        )

-    def add_index(self, model: "Type[Model]", field_names: List[str], unique=False):
+    def add_index(self, model: "Type[Model]", field_names: List[str], unique=False) -> str:
        return self._ADD_INDEX_TEMPLATE.format(
-            unique="UNIQUE" if unique else "",
+            unique="UNIQUE " if unique else "",
            index_name=self.schema_generator._generate_index_name(
                "idx" if not unique else "uid", model, field_names
            ),
            table_name=model._meta.db_table,
-            column_names=", ".join([self.schema_generator.quote(f) for f in field_names]),
+            column_names=", ".join(self.schema_generator.quote(f) for f in field_names),
        )

-    def drop_index(self, model: "Type[Model]", field_names: List[str], unique=False):
+    def drop_index(self, model: "Type[Model]", field_names: List[str], unique=False) -> str:
        return self._DROP_INDEX_TEMPLATE.format(
            index_name=self.schema_generator._generate_index_name(
                "idx" if not unique else "uid", model, field_names
@@ -167,48 +190,68 @@ class BaseDDL:
            table_name=model._meta.db_table,
        )

-    def add_fk(self, model: "Type[Model]", field: ForeignKeyFieldInstance):
-        db_table = model._meta.db_table
-        to_field_name = field.to_field_instance.source_field
-        if not to_field_name:
-            to_field_name = field.to_field_instance.model_field_name
+    def drop_index_by_name(self, model: "Type[Model]", index_name: str) -> str:
+        return self._DROP_INDEX_TEMPLATE.format(
+            index_name=index_name,
+            table_name=model._meta.db_table,
+        )

-        db_column = field.source_field or field.model_field_name + "_id"
-        fk_name = self.schema_generator._generate_fk_name(
+    def _generate_fk_name(
+        self, db_table, field_describe: dict, reference_table_describe: dict
+    ) -> str:
+        """Generate fk name"""
+        db_column = cast(str, field_describe.get("raw_field"))
+        pk_field = cast(dict, reference_table_describe.get("pk_field"))
+        to_field = cast(str, pk_field.get("db_column"))
+        to_table = cast(str, reference_table_describe.get("table"))
+        return self.schema_generator._generate_fk_name(
            from_table=db_table,
            from_field=db_column,
-            to_table=field.related_model._meta.db_table,
-            to_field=to_field_name,
+            to_table=to_table,
+            to_field=to_field,
        )
+
+    def add_fk(
+        self, model: "Type[Model]", field_describe: dict, reference_table_describe: dict
+    ) -> str:
+        db_table = model._meta.db_table
+
+        db_column = field_describe.get("raw_field")
+        pk_field = cast(dict, reference_table_describe.get("pk_field"))
+        reference_id = pk_field.get("db_column")
        return self._ADD_FK_TEMPLATE.format(
            table_name=db_table,
-            fk_name=fk_name,
+            fk_name=self._generate_fk_name(db_table, field_describe, reference_table_describe),
            db_column=db_column,
-            table=field.related_model._meta.db_table,
-            field=to_field_name,
-            on_delete=field.on_delete,
+            table=reference_table_describe.get("table"),
+            field=reference_id,
+            on_delete=field_describe.get("on_delete"),
        )

-    def drop_fk(self, model: "Type[Model]", field: ForeignKeyFieldInstance):
-        to_field_name = field.to_field_instance.source_field
-        if not to_field_name:
-            to_field_name = field.to_field_instance.model_field_name
+    def drop_fk(
+        self, model: "Type[Model]", field_describe: dict, reference_table_describe: dict
+    ) -> str:
        db_table = model._meta.db_table
-        return self._DROP_FK_TEMPLATE.format(
+        fk_name = self._generate_fk_name(db_table, field_describe, reference_table_describe)
+        return self._DROP_FK_TEMPLATE.format(table_name=db_table, fk_name=fk_name)
+
+    def alter_column_default(self, model: "Type[Model]", field_describe: dict) -> str:
+        db_table = model._meta.db_table
+        default = self._get_default(model, field_describe)
+        return self._ALTER_DEFAULT_TEMPLATE.format(
            table_name=db_table,
-            fk_name=self.schema_generator._generate_fk_name(
-                from_table=db_table,
-                from_field=field.source_field or field.model_field_name + "_id",
-                to_table=field.related_model._meta.db_table,
-                to_field=to_field_name,
-            ),
+            column=field_describe.get("db_column"),
+            default="SET" + default if default is not None else "DROP DEFAULT",
        )

-    def alter_column_default(self, model: "Type[Model]", field_object: Field):
-        pass
+    def alter_column_null(self, model: "Type[Model]", field_describe: dict) -> str:
+        return self.modify_column(model, field_describe)

-    def alter_column_null(self, model: "Type[Model]", field_object: Field):
-        pass
+    def set_comment(self, model: "Type[Model]", field_describe: dict) -> str:
+        return self.modify_column(model, field_describe)

-    def set_comment(self, model: "Type[Model]", field_object: Field):
-        pass
+    def rename_table(self, model: "Type[Model]", old_table_name: str, new_table_name: str) -> str:
+        db_table = model._meta.db_table
+        return self._RENAME_TABLE_TEMPLATE.format(
+            table_name=db_table, old_table_name=old_table_name, new_table_name=new_table_name
+        )
--- a/aerich/ddl/mysql/init.py
+++ b/aerich/ddl/mysql/init.py
@@ -1,22 +1,63 @@
+from typing import TYPE_CHECKING, List, Type
+
 from tortoise.backends.mysql.schema_generator import MySQLSchemaGenerator

 from aerich.ddl import BaseDDL

+if TYPE_CHECKING:
+    from tortoise import Model  # noqa:F401
+

 class MysqlDDL(BaseDDL):
    schema_generator_cls = MySQLSchemaGenerator
    DIALECT = MySQLSchemaGenerator.DIALECT
    _DROP_TABLE_TEMPLATE = "DROP TABLE IF EXISTS `{table_name}`"
    _ADD_COLUMN_TEMPLATE = "ALTER TABLE `{table_name}` ADD {column}"
+    _ALTER_DEFAULT_TEMPLATE = "ALTER TABLE `{table_name}` ALTER COLUMN `{column}` {default}"
+    _CHANGE_COLUMN_TEMPLATE = (
+        "ALTER TABLE `{table_name}` CHANGE {old_column_name} {new_column_name} {new_column_type}"
+    )
    _DROP_COLUMN_TEMPLATE = "ALTER TABLE `{table_name}` DROP COLUMN `{column_name}`"
    _RENAME_COLUMN_TEMPLATE = (
        "ALTER TABLE `{table_name}` RENAME COLUMN `{old_column_name}` TO `{new_column_name}`"
    )
    _ADD_INDEX_TEMPLATE = (
-        "ALTER TABLE `{table_name}` ADD {unique} INDEX `{index_name}` ({column_names})"
+        "ALTER TABLE `{table_name}` ADD {unique}INDEX `{index_name}` ({column_names})"
    )
    _DROP_INDEX_TEMPLATE = "ALTER TABLE `{table_name}` DROP INDEX `{index_name}`"
    _ADD_FK_TEMPLATE = "ALTER TABLE `{table_name}` ADD CONSTRAINT `{fk_name}` FOREIGN KEY (`{db_column}`) REFERENCES `{table}` (`{field}`) ON DELETE {on_delete}"
    _DROP_FK_TEMPLATE = "ALTER TABLE `{table_name}` DROP FOREIGN KEY `{fk_name}`"
-    _M2M_TABLE_TEMPLATE = "CREATE TABLE `{table_name}` (`{backward_key}` {backward_type} NOT NULL REFERENCES `{backward_table}` (`{backward_field}`) ON DELETE CASCADE,`{forward_key}` {forward_type} NOT NULL REFERENCES `{forward_table}` (`{forward_field}`) ON DELETE CASCADE){extra}{comment};"
+    _M2M_TABLE_TEMPLATE = (
+        "CREATE TABLE `{table_name}` (\n"
+        "    `{backward_key}` {backward_type} NOT NULL REFERENCES `{backward_table}` (`{backward_field}`) ON DELETE CASCADE,\n"
+        "    `{forward_key}` {forward_type} NOT NULL REFERENCES `{forward_table}` (`{forward_field}`) ON DELETE CASCADE\n"
+        "){extra}{comment}"
+    )
    _MODIFY_COLUMN_TEMPLATE = "ALTER TABLE `{table_name}` MODIFY COLUMN {column}"
+    _RENAME_TABLE_TEMPLATE = "ALTER TABLE `{old_table_name}` RENAME TO `{new_table_name}`"
+
+    def _index_name(self, unique: bool, model: "Type[Model]", field_names: List[str]) -> str:
+        if unique:
+            if len(field_names) == 1:
+                # Example: `email = CharField(max_length=50, unique=True)`
+                # Generate schema: `"email" VARCHAR(10) NOT NULL UNIQUE`
+                # Unique index key is the same as field name: `email`
+                return field_names[0]
+            index_prefix = "uid"
+        else:
+            index_prefix = "idx"
+        return self.schema_generator._generate_index_name(index_prefix, model, field_names)
+
+    def add_index(self, model: "Type[Model]", field_names: List[str], unique=False) -> str:
+        return self._ADD_INDEX_TEMPLATE.format(
+            unique="UNIQUE " if unique else "",
+            index_name=self._index_name(unique, model, field_names),
+            table_name=model._meta.db_table,
+            column_names=", ".join(self.schema_generator.quote(f) for f in field_names),
+        )
+
+    def drop_index(self, model: "Type[Model]", field_names: List[str], unique=False) -> str:
+        return self._DROP_INDEX_TEMPLATE.format(
+            index_name=self._index_name(unique, model, field_names),
+            table_name=model._meta.db_table,
+        )
--- a/aerich/ddl/postgres/init.py
+++ b/aerich/ddl/postgres/init.py
@@ -1,8 +1,7 @@
-from typing import List, Type
+from typing import Type, cast

 from tortoise import Model
 from tortoise.backends.asyncpg.schema_generator import AsyncpgSchemaGenerator
-from tortoise.fields import Field

 from aerich.ddl import BaseDDL

@@ -10,66 +9,43 @@ from aerich.ddl import BaseDDL
 class PostgresDDL(BaseDDL):
    schema_generator_cls = AsyncpgSchemaGenerator
    DIALECT = AsyncpgSchemaGenerator.DIALECT
-    _ADD_INDEX_TEMPLATE = 'CREATE INDEX "{index_name}" ON "{table_name}" ({column_names})'
-    _ADD_UNIQUE_TEMPLATE = (
-        'ALTER TABLE "{table_name}" ADD CONSTRAINT "{index_name}" UNIQUE ({column_names})'
-    )
+    _ADD_INDEX_TEMPLATE = 'CREATE {unique}INDEX "{index_name}" ON "{table_name}" ({column_names})'
    _DROP_INDEX_TEMPLATE = 'DROP INDEX "{index_name}"'
-    _DROP_UNIQUE_TEMPLATE = 'ALTER TABLE "{table_name}" DROP CONSTRAINT "{index_name}"'
-    _ALTER_DEFAULT_TEMPLATE = 'ALTER TABLE "{table_name}" ALTER COLUMN "{column}" {default}'
    _ALTER_NULL_TEMPLATE = 'ALTER TABLE "{table_name}" ALTER COLUMN "{column}" {set_drop} NOT NULL'
-    _MODIFY_COLUMN_TEMPLATE = 'ALTER TABLE "{table_name}" ALTER COLUMN "{column}" TYPE {datatype}'
+    _MODIFY_COLUMN_TEMPLATE = (
+        'ALTER TABLE "{table_name}" ALTER COLUMN "{column}" TYPE {datatype}{using}'
+    )
    _SET_COMMENT_TEMPLATE = 'COMMENT ON COLUMN "{table_name}"."{column}" IS {comment}'
    _DROP_FK_TEMPLATE = 'ALTER TABLE "{table_name}" DROP CONSTRAINT "{fk_name}"'

-    def alter_column_default(self, model: "Type[Model]", field_object: Field):
-        db_table = model._meta.db_table
-        default = self._get_default(model, field_object)
-        return self._ALTER_DEFAULT_TEMPLATE.format(
-            table_name=db_table,
-            column=field_object.model_field_name,
-            default="SET" + default if default else "DROP DEFAULT",
-        )
-
-    def alter_column_null(self, model: "Type[Model]", field_object: Field):
+    def alter_column_null(self, model: "Type[Model]", field_describe: dict) -> str:
        db_table = model._meta.db_table
        return self._ALTER_NULL_TEMPLATE.format(
            table_name=db_table,
-            column=field_object.model_field_name,
-            set_drop="DROP" if field_object.null else "SET",
+            column=field_describe.get("db_column"),
+            set_drop="DROP" if field_describe.get("nullable") else "SET",
        )

-    def modify_column(self, model: "Type[Model]", field_object: Field):
+    def modify_column(self, model: "Type[Model]", field_describe: dict, is_pk: bool = False) -> str:
        db_table = model._meta.db_table
+        db_field_types = cast(dict, field_describe.get("db_field_types"))
+        db_column = field_describe.get("db_column")
+        datatype = db_field_types.get(self.DIALECT) or db_field_types.get("")
        return self._MODIFY_COLUMN_TEMPLATE.format(
            table_name=db_table,
-            column=field_object.model_field_name,
-            datatype=field_object.get_for_dialect(self.DIALECT, "SQL_TYPE"),
+            column=db_column,
+            datatype=datatype,
+            using=f' USING "{db_column}"::{datatype}',
        )

-    def add_index(self, model: "Type[Model]", field_names: List[str], unique=False):
-        template = self._ADD_UNIQUE_TEMPLATE if unique else self._ADD_INDEX_TEMPLATE
-        return template.format(
-            index_name=self.schema_generator._generate_index_name(
-                "uid" if unique else "idx", model, field_names
-            ),
-            table_name=model._meta.db_table,
-            column_names=", ".join([self.schema_generator.quote(f) for f in field_names]),
-        )
-
-    def drop_index(self, model: "Type[Model]", field_names: List[str], unique=False):
-        template = self._DROP_UNIQUE_TEMPLATE if unique else self._DROP_INDEX_TEMPLATE
-        return template.format(
-            index_name=self.schema_generator._generate_index_name(
-                "uid" if unique else "idx", model, field_names
-            ),
-            table_name=model._meta.db_table,
-        )
-
-    def set_comment(self, model: "Type[Model]", field_object: Field):
+    def set_comment(self, model: "Type[Model]", field_describe: dict) -> str:
        db_table = model._meta.db_table
        return self._SET_COMMENT_TEMPLATE.format(
            table_name=db_table,
-            column=field_object.model_field_name,
-            comment="'{}'".format(field_object.description) if field_object.description else "NULL",
+            column=field_describe.get("db_column") or field_describe.get("raw_field"),
+            comment=(
+                "'{}'".format(field_describe.get("description"))
+                if field_describe.get("description")
+                else "NULL"
+            ),
        )
--- a/aerich/ddl/sqlite/init.py
+++ b/aerich/ddl/sqlite/init.py
@@ -2,7 +2,6 @@ from typing import Type

 from tortoise import Model
 from tortoise.backends.sqlite.schema_generator import SqliteSchemaGenerator
-from tortoise.fields import Field

 from aerich.ddl import BaseDDL
 from aerich.exceptions import NotSupportError
@@ -12,8 +11,14 @@ class SqliteDDL(BaseDDL):
    schema_generator_cls = SqliteSchemaGenerator
    DIALECT = SqliteSchemaGenerator.DIALECT

-    def drop_column(self, model: "Type[Model]", column_name: str):
-        raise NotSupportError("Drop column is unsupported in SQLite.")
-
-    def modify_column(self, model: "Type[Model]", field_object: Field):
+    def modify_column(self, model: "Type[Model]", field_object: dict, is_pk: bool = True):
        raise NotSupportError("Modify column is unsupported in SQLite.")
+
+    def alter_column_default(self, model: "Type[Model]", field_describe: dict):
+        raise NotSupportError("Alter column default is unsupported in SQLite.")
+
+    def alter_column_null(self, model: "Type[Model]", field_describe: dict):
+        raise NotSupportError("Alter column null is unsupported in SQLite.")
+
+    def set_comment(self, model: "Type[Model]", field_describe: dict):
+        raise NotSupportError("Alter column comment is unsupported in SQLite.")
--- a/aerich/exceptions.py
+++ b/aerich/exceptions.py
@@ -2,3 +2,9 @@ class NotSupportError(Exception):
    """
    raise when features not support
    """
+
+
+class DowngradeError(Exception):
+    """
+    raise when downgrade error
+    """
--- a/aerich/inspectdb.py
+++ b/aerich/inspectdb.py
@@ -1,85 +0,0 @@
-import sys
-from typing import List, Optional
-
-from ddlparse import DdlParse
-from tortoise import BaseDBAsyncClient
-
-
-class InspectDb:
-    _table_template = "class {table}(Model):\n"
-    _field_template_mapping = {
-        "INT": "    {field} = fields.IntField({pk}{unique}{comment})",
-        "SMALLINT": "    {field} = fields.IntField({pk}{unique}{comment})",
-        "TINYINT": "    {field} = fields.BooleanField({null}{default}{comment})",
-        "VARCHAR": "    {field} = fields.CharField({pk}{unique}{length}{null}{default}{comment})",
-        "LONGTEXT": "    {field} = fields.TextField({null}{default}{comment})",
-        "TEXT": "    {field} = fields.TextField({null}{default}{comment})",
-        "DATETIME": "    {field} = fields.DatetimeField({null}{default}{comment})",
-    }
-
-    def __init__(self, conn: BaseDBAsyncClient, tables: Optional[List[str]] = None):
-        self.conn = conn
-        self.tables = tables
-        self.DIALECT = conn.schema_generator.DIALECT
-
-    async def show_create_tables(self):
-        if self.DIALECT == "mysql":
-            if not self.tables:
-                sql_tables = f"SELECT table_name FROM information_schema.tables WHERE table_schema = '{self.conn.database}';"  # nosec: B608
-                ret = await self.conn.execute_query(sql_tables)
-                self.tables = map(lambda x: x["TABLE_NAME"], ret[1])
-            for table in self.tables:
-                sql_show_create_table = f"SHOW CREATE TABLE {table}"
-                ret = await self.conn.execute_query(sql_show_create_table)
-                yield ret[1][0]["Create Table"]
-        else:
-            raise NotImplementedError("Currently only support MySQL")
-
-    async def inspect(self):
-        ddl_list = self.show_create_tables()
-        result = "from tortoise import Model, fields\n\n\n"
-        tables = []
-        async for ddl in ddl_list:
-            parser = DdlParse(ddl, DdlParse.DATABASE.mysql)
-            table = parser.parse()
-            name = table.name.title()
-            columns = table.columns
-            fields = []
-            model = self._table_template.format(table=name)
-            for column_name, column in columns.items():
-                comment = default = length = unique = null = pk = ""
-                if column.primary_key:
-                    pk = "pk=True, "
-                if column.unique:
-                    unique = "unique=True, "
-                if column.data_type == "VARCHAR":
-                    length = f"max_length={column.length}, "
-                if not column.not_null:
-                    null = "null=True, "
-                if column.default is not None:
-                    if column.data_type == "TINYINT":
-                        default = f"default={'True' if column.default == '1' else 'False'}, "
-                    elif column.data_type == "DATETIME":
-                        if "CURRENT_TIMESTAMP" in column.default:
-                            if "ON UPDATE CURRENT_TIMESTAMP" in ddl:
-                                default = "auto_now_add=True, "
-                            else:
-                                default = "auto_now=True, "
-                    else:
-                        default = f"default={column.default}, "
-
-                if column.comment:
-                    comment = f"description='{column.comment}', "
-
-                field = self._field_template_mapping[column.data_type].format(
-                    field=column_name,
-                    pk=pk,
-                    unique=unique,
-                    length=length,
-                    null=null,
-                    default=default,
-                    comment=comment,
-                )
-                fields.append(field)
-            tables.append(model + "\n".join(fields))
-        sys.stdout.write(result + "\n\n\n".join(tables))
--- a/aerich/inspectdb/init.py
+++ b/aerich/inspectdb/init.py
@@ -0,0 +1,186 @@
+from __future__ import annotations
+
+from typing import Any, Callable, Dict, Optional, TypedDict
+
+from pydantic import BaseModel
+from tortoise import BaseDBAsyncClient
+
+
+class ColumnInfoDict(TypedDict):
+    name: str
+    pk: str
+    index: str
+    null: str
+    default: str
+    length: str
+    comment: str
+
+
+FieldMapDict = Dict[str, Callable[..., str]]
+
+
+class Column(BaseModel):
+    name: str
+    data_type: str
+    null: bool
+    default: Any
+    comment: Optional[str] = None
+    pk: bool
+    unique: bool
+    index: bool
+    length: Optional[int] = None
+    extra: Optional[str] = None
+    decimal_places: Optional[int] = None
+    max_digits: Optional[int] = None
+
+    def translate(self) -> ColumnInfoDict:
+        comment = default = length = index = null = pk = ""
+        if self.pk:
+            pk = "pk=True, "
+        else:
+            if self.unique:
+                index = "unique=True, "
+            else:
+                if self.index:
+                    index = "index=True, "
+        if self.data_type in ("varchar", "VARCHAR"):
+            length = f"max_length={self.length}, "
+        elif self.data_type in ("decimal", "numeric"):
+            length_parts = []
+            if self.max_digits:
+                length_parts.append(f"max_digits={self.max_digits}")
+            if self.decimal_places:
+                length_parts.append(f"decimal_places={self.decimal_places}")
+            if length_parts:
+                length = ", ".join(length_parts) + ", "
+        if self.null:
+            null = "null=True, "
+        if self.default is not None:
+            if self.data_type in ("tinyint", "INT"):
+                default = f"default={'True' if self.default == '1' else 'False'}, "
+            elif self.data_type == "bool":
+                default = f"default={'True' if self.default == 'true' else 'False'}, "
+            elif self.data_type in ("datetime", "timestamptz", "TIMESTAMP"):
+                if "CURRENT_TIMESTAMP" == self.default:
+                    if "DEFAULT_GENERATED on update CURRENT_TIMESTAMP" == self.extra:
+                        default = "auto_now=True, "
+                    else:
+                        default = "auto_now_add=True, "
+            else:
+                if "::" in self.default:
+                    default = f"default={self.default.split('::')[0]}, "
+                elif self.default.endswith("()"):
+                    default = ""
+                elif self.default == "":
+                    default = 'default=""'
+                else:
+                    default = f"default={self.default}, "
+
+        if self.comment:
+            comment = f"description='{self.comment}', "
+        return {
+            "name": self.name,
+            "pk": pk,
+            "index": index,
+            "null": null,
+            "default": default,
+            "length": length,
+            "comment": comment,
+        }
+
+
+class Inspect:
+    _table_template = "class {table}(Model):\n"
+
+    def __init__(self, conn: BaseDBAsyncClient, tables: list[str] | None = None) -> None:
+        self.conn = conn
+        try:
+            self.database = conn.database  # type:ignore[attr-defined]
+        except AttributeError:
+            pass
+        self.tables = tables
+
+    @property
+    def field_map(self) -> FieldMapDict:
+        raise NotImplementedError
+
+    async def inspect(self) -> str:
+        if not self.tables:
+            self.tables = await self.get_all_tables()
+        result = "from tortoise import Model, fields\n\n\n"
+        tables = []
+        for table in self.tables:
+            columns = await self.get_columns(table)
+            fields = []
+            model = self._table_template.format(table=table.title().replace("_", ""))
+            for column in columns:
+                field = self.field_map[column.data_type](**column.translate())
+                fields.append("    " + field)
+            tables.append(model + "\n".join(fields))
+        return result + "\n\n\n".join(tables)
+
+    async def get_columns(self, table: str) -> list[Column]:
+        raise NotImplementedError
+
+    async def get_all_tables(self) -> list[str]:
+        raise NotImplementedError
+
+    @classmethod
+    def decimal_field(cls, **kwargs) -> str:
+        return "{name} = fields.DecimalField({pk}{index}{length}{null}{default}{comment})".format(
+            **kwargs
+        )
+
+    @classmethod
+    def time_field(cls, **kwargs) -> str:
+        return "{name} = fields.TimeField({null}{default}{comment})".format(**kwargs)
+
+    @classmethod
+    def date_field(cls, **kwargs) -> str:
+        return "{name} = fields.DateField({null}{default}{comment})".format(**kwargs)
+
+    @classmethod
+    def float_field(cls, **kwargs) -> str:
+        return "{name} = fields.FloatField({null}{default}{comment})".format(**kwargs)
+
+    @classmethod
+    def datetime_field(cls, **kwargs) -> str:
+        return "{name} = fields.DatetimeField({null}{default}{comment})".format(**kwargs)
+
+    @classmethod
+    def text_field(cls, **kwargs) -> str:
+        return "{name} = fields.TextField({null}{default}{comment})".format(**kwargs)
+
+    @classmethod
+    def char_field(cls, **kwargs) -> str:
+        return "{name} = fields.CharField({pk}{index}{length}{null}{default}{comment})".format(
+            **kwargs
+        )
+
+    @classmethod
+    def int_field(cls, **kwargs) -> str:
+        return "{name} = fields.IntField({pk}{index}{comment})".format(**kwargs)
+
+    @classmethod
+    def smallint_field(cls, **kwargs) -> str:
+        return "{name} = fields.SmallIntField({pk}{index}{comment})".format(**kwargs)
+
+    @classmethod
+    def bigint_field(cls, **kwargs) -> str:
+        return "{name} = fields.BigIntField({pk}{index}{default}{comment})".format(**kwargs)
+
+    @classmethod
+    def bool_field(cls, **kwargs) -> str:
+        return "{name} = fields.BooleanField({null}{default}{comment})".format(**kwargs)
+
+    @classmethod
+    def uuid_field(cls, **kwargs) -> str:
+        return "{name} = fields.UUIDField({pk}{index}{default}{comment})".format(**kwargs)
+
+    @classmethod
+    def json_field(cls, **kwargs) -> str:
+        return "{name} = fields.JSONField({null}{default}{comment})".format(**kwargs)
+
+    @classmethod
+    def binary_field(cls, **kwargs) -> str:
+        return "{name} = fields.BinaryField({null}{default}{comment})".format(**kwargs)
--- a/aerich/inspectdb/mysql.py
+++ b/aerich/inspectdb/mysql.py
@@ -0,0 +1,71 @@
+from __future__ import annotations
+
+from aerich.inspectdb import Column, FieldMapDict, Inspect
+
+
+class InspectMySQL(Inspect):
+    @property
+    def field_map(self) -> FieldMapDict:
+        return {
+            "int": self.int_field,
+            "smallint": self.smallint_field,
+            "tinyint": self.bool_field,
+            "bigint": self.bigint_field,
+            "varchar": self.char_field,
+            "char": self.char_field,
+            "longtext": self.text_field,
+            "text": self.text_field,
+            "datetime": self.datetime_field,
+            "float": self.float_field,
+            "date": self.date_field,
+            "time": self.time_field,
+            "decimal": self.decimal_field,
+            "json": self.json_field,
+            "longblob": self.binary_field,
+        }
+
+    async def get_all_tables(self) -> list[str]:
+        sql = "select TABLE_NAME from information_schema.TABLES where TABLE_SCHEMA=%s"
+        ret = await self.conn.execute_query_dict(sql, [self.database])
+        return list(map(lambda x: x["TABLE_NAME"], ret))
+
+    async def get_columns(self, table: str) -> list[Column]:
+        columns = []
+        sql = """select c.*, s.NON_UNIQUE, s.INDEX_NAME
+from information_schema.COLUMNS c
+         left join information_schema.STATISTICS s on c.TABLE_NAME = s.TABLE_NAME
+    and c.TABLE_SCHEMA = s.TABLE_SCHEMA
+    and c.COLUMN_NAME = s.COLUMN_NAME
+where c.TABLE_SCHEMA = %s
+  and c.TABLE_NAME = %s"""
+        ret = await self.conn.execute_query_dict(sql, [self.database, table])
+        for row in ret:
+            non_unique = row["NON_UNIQUE"]
+            if non_unique is None:
+                unique = False
+            else:
+                unique = not non_unique
+            index_name = row["INDEX_NAME"]
+            if index_name is None:
+                index = False
+            else:
+                index = row["INDEX_NAME"] != "PRIMARY"
+            columns.append(
+                Column(
+                    name=row["COLUMN_NAME"],
+                    data_type=row["DATA_TYPE"],
+                    null=row["IS_NULLABLE"] == "YES",
+                    default=row["COLUMN_DEFAULT"],
+                    pk=row["COLUMN_KEY"] == "PRI",
+                    comment=row["COLUMN_COMMENT"],
+                    unique=row["COLUMN_KEY"] == "UNI",
+                    extra=row["EXTRA"],
+                    # TODO: why `unque`?
+                    unque=unique,  # type:ignore
+                    index=index,
+                    length=row["CHARACTER_MAXIMUM_LENGTH"],
+                    max_digits=row["NUMERIC_PRECISION"],
+                    decimal_places=row["NUMERIC_SCALE"],
+                )
+            )
+        return columns
--- a/aerich/inspectdb/postgres.py
+++ b/aerich/inspectdb/postgres.py
@@ -0,0 +1,79 @@
+from __future__ import annotations
+
+from typing import TYPE_CHECKING
+
+from aerich.inspectdb import Column, FieldMapDict, Inspect
+
+if TYPE_CHECKING:
+    from tortoise.backends.base_postgres.client import BasePostgresClient
+
+
+class InspectPostgres(Inspect):
+    def __init__(self, conn: "BasePostgresClient", tables: list[str] | None = None) -> None:
+        super().__init__(conn, tables)
+        self.schema = conn.server_settings.get("schema") or "public"
+
+    @property
+    def field_map(self) -> FieldMapDict:
+        return {
+            "int4": self.int_field,
+            "int8": self.int_field,
+            "smallint": self.smallint_field,
+            "varchar": self.char_field,
+            "text": self.text_field,
+            "bigint": self.bigint_field,
+            "timestamptz": self.datetime_field,
+            "float4": self.float_field,
+            "float8": self.float_field,
+            "date": self.date_field,
+            "time": self.time_field,
+            "decimal": self.decimal_field,
+            "numeric": self.decimal_field,
+            "uuid": self.uuid_field,
+            "jsonb": self.json_field,
+            "bytea": self.binary_field,
+            "bool": self.bool_field,
+            "timestamp": self.datetime_field,
+        }
+
+    async def get_all_tables(self) -> list[str]:
+        sql = "select TABLE_NAME from information_schema.TABLES where table_catalog=$1 and table_schema=$2"
+        ret = await self.conn.execute_query_dict(sql, [self.database, self.schema])
+        return list(map(lambda x: x["table_name"], ret))
+
+    async def get_columns(self, table: str) -> list[Column]:
+        columns = []
+        sql = f"""select c.column_name,
+       col_description('public.{table}'::regclass, ordinal_position) as column_comment,
+       t.constraint_type as column_key,
+       udt_name as data_type,
+       is_nullable,
+       column_default,
+       character_maximum_length,
+       numeric_precision,
+       numeric_scale
+from information_schema.constraint_column_usage const
+         join information_schema.table_constraints t
+              using (table_catalog, table_schema, table_name, constraint_catalog, constraint_schema, constraint_name)
+         right join information_schema.columns c using (column_name, table_catalog, table_schema, table_name)
+where c.table_catalog = $1
+  and c.table_name = $2
+  and c.table_schema = $3"""  # nosec:B608
+        ret = await self.conn.execute_query_dict(sql, [self.database, table, self.schema])
+        for row in ret:
+            columns.append(
+                Column(
+                    name=row["column_name"],
+                    data_type=row["data_type"],
+                    null=row["is_nullable"] == "YES",
+                    default=row["column_default"],
+                    length=row["character_maximum_length"],
+                    max_digits=row["numeric_precision"],
+                    decimal_places=row["numeric_scale"],
+                    comment=row["column_comment"],
+                    pk=row["column_key"] == "PRIMARY KEY",
+                    unique=False,  # can't get this simply
+                    index=False,  # can't get this simply
+                )
+            )
+        return columns
--- a/aerich/inspectdb/sqlite.py
+++ b/aerich/inspectdb/sqlite.py
@@ -0,0 +1,61 @@
+from __future__ import annotations
+
+from aerich.inspectdb import Column, FieldMapDict, Inspect
+
+
+class InspectSQLite(Inspect):
+    @property
+    def field_map(self) -> FieldMapDict:
+        return {
+            "INTEGER": self.int_field,
+            "INT": self.bool_field,
+            "SMALLINT": self.smallint_field,
+            "VARCHAR": self.char_field,
+            "TEXT": self.text_field,
+            "TIMESTAMP": self.datetime_field,
+            "REAL": self.float_field,
+            "BIGINT": self.bigint_field,
+            "DATE": self.date_field,
+            "TIME": self.time_field,
+            "JSON": self.json_field,
+            "BLOB": self.binary_field,
+        }
+
+    async def get_columns(self, table: str) -> list[Column]:
+        columns = []
+        sql = f"PRAGMA table_info({table})"
+        ret = await self.conn.execute_query_dict(sql)
+        columns_index = await self._get_columns_index(table)
+        for row in ret:
+            try:
+                length = row["type"].split("(")[1].split(")")[0]
+            except IndexError:
+                length = None
+            columns.append(
+                Column(
+                    name=row["name"],
+                    data_type=row["type"].split("(")[0],
+                    null=row["notnull"] == 0,
+                    default=row["dflt_value"],
+                    length=length,
+                    pk=row["pk"] == 1,
+                    unique=columns_index.get(row["name"]) == "unique",
+                    index=columns_index.get(row["name"]) == "index",
+                )
+            )
+        return columns
+
+    async def _get_columns_index(self, table: str) -> dict[str, str]:
+        sql = f"PRAGMA index_list ({table})"
+        indexes = await self.conn.execute_query_dict(sql)
+        ret = {}
+        for index in indexes:
+            sql = f"PRAGMA index_info({index['name']})"
+            index_info = (await self.conn.execute_query_dict(sql))[0]
+            ret[index_info["name"]] = "unique" if index["unique"] else "index"
+        return ret
+
+    async def get_all_tables(self) -> list[str]:
+        sql = "select tbl_name from sqlite_master where type='table' and name!='sqlite_sequence'"
+        ret = await self.conn.execute_query_dict(sql)
+        return list(map(lambda x: x["tbl_name"], ret))
--- a/aerich/migrate.py
+++ b/aerich/migrate.py
--- a/aerich/models.py
+++ b/aerich/models.py
@@ -1,12 +1,15 @@
 from tortoise import Model, fields

+from aerich.coder import decoder, encoder
+
 MAX_VERSION_LENGTH = 255
+MAX_APP_LENGTH = 100


 class Aerich(Model):
    version = fields.CharField(max_length=MAX_VERSION_LENGTH)
-    app = fields.CharField(max_length=20)
-    content = fields.TextField()
+    app = fields.CharField(max_length=MAX_APP_LENGTH)
+    content: dict = fields.JSONField(encoder=encoder, decoder=decoder)

    class Meta:
        ordering = ["-id"]
--- a/aerich/utils.py
+++ b/aerich/utils.py
@@ -1,10 +1,31 @@
-import importlib
-from typing import Dict
+import importlib.util
+import os
+import re
+import sys
+from pathlib import Path
+from types import ModuleType
+from typing import Dict, Optional, Union

-from click import BadOptionUsage, Context
+from asyncclick import BadOptionUsage, ClickException, Context
 from tortoise import BaseDBAsyncClient, Tortoise


+def add_src_path(path: str) -> str:
+    """
+    add a folder to the paths, so we can import from there
+    :param path: path to add
+    :return: absolute path
+    """
+    if not os.path.isabs(path):
+        # use the absolute path, otherwise some other things (e.g. __file__) won't work properly
+        path = os.path.abspath(path)
+    if not os.path.isdir(path):
+        raise ClickException(f"Specified source folder does not exist: {path}")
+    if path not in sys.path:
+        sys.path.insert(0, path)
+    return path
+
+
 def get_app_connection_name(config, app_name: str) -> str:
    """
    get connection name
@@ -41,12 +62,11 @@ def get_tortoise_config(ctx: Context, tortoise_orm: str) -> dict:
    splits = tortoise_orm.split(".")
    config_path = ".".join(splits[:-1])
    tortoise_config = splits[-1]
+
    try:
        config_module = importlib.import_module(config_path)
-    except (ModuleNotFoundError, AttributeError):
-        raise BadOptionUsage(
-            ctx=ctx, message=f'No config named "{config_path}"', option_name="--config"
-        )
+    except ModuleNotFoundError as e:
+        raise ClickException(f"Error while importing configuration module: {e}") from None

    config = getattr(config_module, tortoise_config, None)
    if not config:
@@ -58,53 +78,26 @@ def get_tortoise_config(ctx: Context, tortoise_orm: str) -> dict:
    return config


-_UPGRADE = "-- upgrade --\n"
-_DOWNGRADE = "-- downgrade --\n"
-
-
-def get_version_content_from_file(version_file: str) -> Dict:
+def get_models_describe(app: str) -> Dict:
    """
-    get version content
-    :param version_file:
+    get app models describe
+    :param app:
    :return:
    """
-    with open(version_file, "r", encoding="utf-8") as f:
-        content = f.read()
-        first = content.index(_UPGRADE)
-        try:
-            second = content.index(_DOWNGRADE)
-        except ValueError:
-            second = len(content) - 1
-        upgrade_content = content[first + len(_UPGRADE) : second].strip()  # noqa:E203
-        downgrade_content = content[second + len(_DOWNGRADE) :].strip()  # noqa:E203
-        ret = {
-            "upgrade": list(filter(lambda x: x or False, upgrade_content.split(";\n"))),
-            "downgrade": list(filter(lambda x: x or False, downgrade_content.split(";\n"))),
-        }
-        return ret
+    ret = {}
+    for model in Tortoise.apps[app].values():
+        describe = model.describe()
+        ret[describe.get("name")] = describe
+    return ret


-def write_version_file(version_file: str, content: Dict):
-    """
-    write version file
-    :param version_file:
-    :param content:
-    :return:
-    """
-    with open(version_file, "w", encoding="utf-8") as f:
-        f.write(_UPGRADE)
-        upgrade = content.get("upgrade")
-        if len(upgrade) > 1:
-            f.write(";\n".join(upgrade) + ";\n")
-        else:
-            f.write(f"{upgrade[0]}")
-            if not upgrade[0].endswith(";"):
-                f.write(";")
-            f.write("\n")
-        downgrade = content.get("downgrade")
-        if downgrade:
-            f.write(_DOWNGRADE)
-            if len(downgrade) > 1:
-                f.write(";\n".join(downgrade) + ";\n")
-            else:
-                f.write(f"{downgrade[0]};\n")
+def is_default_function(string: str) -> Optional[re.Match]:
+    return re.match(r"^<function.+>$", str(string or ""))
+
+
+def import_py_file(file: Union[str, Path]) -> ModuleType:
+    module_name, file_ext = os.path.splitext(os.path.split(file)[-1])
+    spec = importlib.util.spec_from_file_location(module_name, file)
+    module = importlib.util.module_from_spec(spec)  # type:ignore[arg-type]
+    spec.loader.exec_module(module)  # type:ignore[union-attr]
+    return module
--- a/aerich/version.py
+++ b/aerich/version.py
@@ -0,0 +1 @@
+__version__ = "0.8.0"
--- a/conftest.py
+++ b/conftest.py
@@ -1,19 +1,22 @@
 import asyncio
 import os
+from typing import Generator

 import pytest
 from tortoise import Tortoise, expand_db_url, generate_schema_for_client
 from tortoise.backends.asyncpg.schema_generator import AsyncpgSchemaGenerator
 from tortoise.backends.mysql.schema_generator import MySQLSchemaGenerator
 from tortoise.backends.sqlite.schema_generator import SqliteSchemaGenerator
+from tortoise.exceptions import DBConnectionError, OperationalError

 from aerich.ddl.mysql import MysqlDDL
 from aerich.ddl.postgres import PostgresDDL
 from aerich.ddl.sqlite import SqliteDDL
 from aerich.migrate import Migrate

-db_url = os.getenv("TEST_DB", "sqlite://:memory:")
-db_url_second = os.getenv("TEST_DB_SECOND", "sqlite://:memory:")
+MEMORY_SQLITE = "sqlite://:memory:"
+db_url = os.getenv("TEST_DB", MEMORY_SQLITE)
+db_url_second = os.getenv("TEST_DB_SECOND", MEMORY_SQLITE)
 tortoise_orm = {
    "connections": {
        "default": expand_db_url(db_url, True),
@@ -27,7 +30,7 @@ tortoise_orm = {


@pytest.fixture(scope="function", autouse=True)
-def reset_migrate():
+def reset_migrate() -> None:
    Migrate.upgrade_operators = []
    Migrate.downgrade_operators = []
    Migrate._upgrade_fk_m2m_index_operators = []
@@ -37,26 +40,27 @@ def reset_migrate():


@pytest.fixture(scope="session")
-def event_loop():
+def event_loop() -> Generator:
    policy = asyncio.get_event_loop_policy()
    res = policy.new_event_loop()
    asyncio.set_event_loop(res)
-    res._close = res.close
-    res.close = lambda: None
+    res._close = res.close  # type:ignore[attr-defined]
+    res.close = lambda: None  # type:ignore[method-assign]

    yield res

-    res._close()
+    res._close()  # type:ignore[attr-defined]


@pytest.fixture(scope="session", autouse=True)
-async def initialize_tests(event_loop, request):
-    tortoise_orm["connections"]["diff_models"] = "sqlite://:memory:"
-    tortoise_orm["apps"]["diff_models"] = {
-        "models": ["tests.diff_models"],
-        "default_connection": "diff_models",
-    }
-
+async def initialize_tests(event_loop, request) -> None:
+    # Placing init outside the try block since it doesn't
+    # establish connections to the DB eagerly.
+    await Tortoise.init(config=tortoise_orm)
+    try:
+        await Tortoise._drop_databases()
+    except (DBConnectionError, OperationalError):
+        pass
    await Tortoise.init(config=tortoise_orm, _create_db=True)
    await generate_schema_for_client(Tortoise.get_connection("default"), safe=True)

--- a/images/alipay.jpeg
+++ b/images/alipay.jpeg
--- a/images/wechatpay.jpeg
+++ b/images/wechatpay.jpeg
--- a/poetry.lock
+++ b/poetry.lock
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,13 +1,13 @@
 [tool.poetry]
 name = "aerich"
-version = "0.4.4"
+version = "0.8.0"
 description = "A database migrations tool for Tortoise ORM."
 authors = ["long2ice <long2ice@gmail.com>"]
 license = "Apache-2.0"
 readme = "README.md"
-homepage = "https://github.com/long2ice/aerich"
-repository = "https://github.com/long2ice/aerich.git"
-documentation = "https://github.com/long2ice/aerich"
+homepage = "https://github.com/tortoise/aerich"
+repository = "https://github.com/tortoise/aerich.git"
+documentation = "https://github.com/tortoise/aerich"
 keywords = ["migrate", "Tortoise-ORM", "mysql"]
 packages = [
    { include = "aerich" }
@@ -15,30 +15,57 @@ packages = [
 include = ["CHANGELOG.md", "LICENSE", "README.md"]

 [tool.poetry.dependencies]
-python = "^3.7"
+python = "^3.8"
 tortoise-orm = "*"
-click = "*"
-pydantic = "*"
-aiomysql = {version = "*", optional = true}
-asyncpg = {version = "*", optional = true}
-ddlparse = "*"
+asyncpg = { version = "*", optional = true }
+asyncmy = { version = "^0.2.9", optional = true, allow-prereleases = true }
+pydantic = "^2.0"
+dictdiffer = "*"
+tomlkit = "*"
+asyncclick = "^8.1.7.2"

-[tool.poetry.dev-dependencies]
-flake8 = "*"
+[tool.poetry.group.dev.dependencies]
+ruff = "*"
 isort = "*"
-black = "^20.8b1"
+black = "*"
 pytest = "*"
 pytest-xdist = "*"
-pytest-asyncio = "*"
+# Breaking change in 0.23.*
+# https://github.com/pytest-dev/pytest-asyncio/issues/706
+pytest-asyncio = "^0.21.2"
 bandit = "*"
 pytest-mock = "*"
+cryptography = "*"
+mypy = "^1.10.0"

 [tool.poetry.extras]
-dbdrivers = ["aiomysql", "asyncpg"]
+asyncmy = ["asyncmy"]
+asyncpg = ["asyncpg"]
+
+
+[tool.aerich]
+tortoise_orm = "conftest.tortoise_orm"
+location = "./migrations"
+src_folder = "./."

 [build-system]
-requires = ["poetry>=0.12"]
-build-backend = "poetry.masonry.api"
+requires = ["poetry-core>=1.0.0"]
+build-backend = "poetry.core.masonry.api"

 [tool.poetry.scripts]
 aerich = "aerich.cli:main"
+
+[tool.black]
+line-length = 100
+target-version = ['py38', 'py39', 'py310', 'py311', 'py312']
+
+[tool.pytest.ini_options]
+asyncio_mode = 'auto'
+
+[tool.mypy]
+pretty = true
+python_version = "3.8"
+ignore_missing_imports = true
+
+[tool.ruff.lint]
+ignore = ['E501']
--- a/setup.cfg
+++ b/setup.cfg
@@ -1,2 +0,0 @@
-[flake8]
-ignore = E501,W503
--- a/tests/models.py
+++ b/tests/models.py
@@ -1,4 +1,5 @@
 import datetime
+import uuid
 from enum import IntEnum

 from tortoise import Model, fields
@@ -23,41 +24,63 @@ class Status(IntEnum):

 class User(Model):
    username = fields.CharField(max_length=20, unique=True)
-    password = fields.CharField(max_length=200)
+    password = fields.CharField(max_length=100)
    last_login = fields.DatetimeField(description="Last Login", default=datetime.datetime.now)
    is_active = fields.BooleanField(default=True, description="Is Active")
    is_superuser = fields.BooleanField(default=False, description="Is SuperUser")
-    avatar = fields.CharField(max_length=200, default="")
    intro = fields.TextField(default="")
+    longitude = fields.DecimalField(max_digits=10, decimal_places=8)


 class Email(Model):
-    email = fields.CharField(max_length=200)
+    email_id = fields.IntField(primary_key=True)
+    email = fields.CharField(max_length=200, db_index=True)
    is_primary = fields.BooleanField(default=False)
-    user = fields.ForeignKeyField("models.User", db_constraint=False)
+    address = fields.CharField(max_length=200)
+    users: fields.ManyToManyRelation[User] = fields.ManyToManyField("models.User")
+
+
+def default_name():
+    return uuid.uuid4()


 class Category(Model):
-    slug = fields.CharField(max_length=200)
-    name = fields.CharField(max_length=200)
-    user = fields.ForeignKeyField("models.User", description="User")
+    slug = fields.CharField(max_length=100)
+    name = fields.CharField(max_length=200, null=True, default=default_name)
+    user: fields.ForeignKeyRelation[User] = fields.ForeignKeyField(
+        "models.User", description="User"
+    )
+    title = fields.CharField(max_length=20, unique=False)
    created_at = fields.DatetimeField(auto_now_add=True)


 class Product(Model):
-    categories = fields.ManyToManyField("models.Category")
+    categories: fields.ManyToManyRelation[Category] = fields.ManyToManyField("models.Category")
    name = fields.CharField(max_length=50)
-    view_num = fields.IntField(description="View Num")
+    view_num = fields.IntField(description="View Num", default=0)
    sort = fields.IntField()
    is_reviewed = fields.BooleanField(description="Is Reviewed")
-    type = fields.IntEnumField(ProductType, description="Product Type")
-    image = fields.CharField(max_length=200)
+    type = fields.IntEnumField(
+        ProductType, description="Product Type", source_field="type_db_alias"
+    )
+    pic = fields.CharField(max_length=200)
    body = fields.TextField()
    created_at = fields.DatetimeField(auto_now_add=True)

+    class Meta:
+        unique_together = (("name", "type"),)
+        indexes = (("name", "type"),)
+

 class Config(Model):
    label = fields.CharField(max_length=200)
    key = fields.CharField(max_length=20)
-    value = fields.JSONField()
-    status: Status = fields.IntEnumField(Status, default=Status.on)
+    value: dict = fields.JSONField()
+    status: Status = fields.IntEnumField(Status)
+    user: fields.ForeignKeyRelation[User] = fields.ForeignKeyField(
+        "models.User", description="User"
+    )
+
+
+class NewModel(Model):
+    name = fields.CharField(max_length=50)
--- a/tests/models_second.py
+++ b/tests/models_second.py
@@ -34,23 +34,31 @@ class User(Model):
 class Email(Model):
    email = fields.CharField(max_length=200)
    is_primary = fields.BooleanField(default=False)
-    user = fields.ForeignKeyField("models_second.User", db_constraint=False)
+    user: fields.ForeignKeyRelation[User] = fields.ForeignKeyField(
+        "models_second.User", db_constraint=False
+    )


 class Category(Model):
    slug = fields.CharField(max_length=200)
    name = fields.CharField(max_length=200)
-    user = fields.ForeignKeyField("models_second.User", description="User")
+    user: fields.ForeignKeyRelation[User] = fields.ForeignKeyField(
+        "models_second.User", description="User"
+    )
    created_at = fields.DatetimeField(auto_now_add=True)


 class Product(Model):
-    categories = fields.ManyToManyField("models_second.Category")
+    categories: fields.ManyToManyRelation[Category] = fields.ManyToManyField(
+        "models_second.Category"
+    )
    name = fields.CharField(max_length=50)
    view_num = fields.IntField(description="View Num")
    sort = fields.IntField()
    is_reviewed = fields.BooleanField(description="Is Reviewed")
-    type = fields.IntEnumField(ProductType, description="Product Type")
+    type = fields.IntEnumField(
+        ProductType, description="Product Type", source_field="type_db_alias"
+    )
    image = fields.CharField(max_length=200)
    body = fields.TextField()
    created_at = fields.DatetimeField(auto_now_add=True)
@@ -59,5 +67,5 @@ class Product(Model):
 class Config(Model):
    label = fields.CharField(max_length=200)
    key = fields.CharField(max_length=20)
-    value = fields.JSONField()
+    value: dict = fields.JSONField()
    status: Status = fields.IntEnumField(Status, default=Status.on)
--- a/tests/diff_models.py
+++ b/tests/diff_models.py
@@ -24,39 +24,52 @@ class Status(IntEnum):
 class User(Model):
    username = fields.CharField(max_length=20)
    password = fields.CharField(max_length=200)
-    last_login_at = fields.DatetimeField(description="Last Login", default=datetime.datetime.now)
+    last_login = fields.DatetimeField(description="Last Login", default=datetime.datetime.now)
    is_active = fields.BooleanField(default=True, description="Is Active")
    is_superuser = fields.BooleanField(default=False, description="Is SuperUser")
    avatar = fields.CharField(max_length=200, default="")
    intro = fields.TextField(default="")
+    longitude = fields.DecimalField(max_digits=12, decimal_places=9)


 class Email(Model):
    email = fields.CharField(max_length=200)
    is_primary = fields.BooleanField(default=False)
-    user = fields.ForeignKeyField("diff_models.User", db_constraint=True)
+    user: fields.ForeignKeyRelation[User] = fields.ForeignKeyField(
+        "models.User", db_constraint=False
+    )


 class Category(Model):
    slug = fields.CharField(max_length=200)
-    user = fields.ForeignKeyField("diff_models.User", description="User")
+    name = fields.CharField(max_length=200)
+    user: fields.ForeignKeyRelation[User] = fields.ForeignKeyField(
+        "models.User", description="User"
+    )
    created_at = fields.DatetimeField(auto_now_add=True)


 class Product(Model):
-    categories = fields.ManyToManyField("diff_models.Category")
+    categories: fields.ManyToManyRelation[Category] = fields.ManyToManyField("models.Category")
+    uid = fields.IntField(source_field="uuid", unique=True)
    name = fields.CharField(max_length=50)
    view_num = fields.IntField(description="View Num")
    sort = fields.IntField()
    is_reviewed = fields.BooleanField(description="Is Reviewed")
-    type = fields.IntEnumField(ProductType, description="Product Type")
+    type = fields.IntEnumField(
+        ProductType, description="Product Type", source_field="type_db_alias"
+    )
    image = fields.CharField(max_length=200)
    body = fields.TextField()
    created_at = fields.DatetimeField(auto_now_add=True)


 class Config(Model):
+    name = fields.CharField(max_length=100, unique=True)
    label = fields.CharField(max_length=200)
    key = fields.CharField(max_length=20)
-    value = fields.JSONField()
+    value: dict = fields.JSONField()
    status: Status = fields.IntEnumField(Status, default=Status.on)
+
+    class Meta:
+        table = "configs"
--- a/tests/test_ddl.py
+++ b/tests/test_ddl.py
@@ -1,11 +1,8 @@
-import pytest
-
 from aerich.ddl.mysql import MysqlDDL
 from aerich.ddl.postgres import PostgresDDL
 from aerich.ddl.sqlite import SqliteDDL
-from aerich.exceptions import NotSupportError
 from aerich.migrate import Migrate
-from tests.models import Category, User
+from tests.models import Category, Product, User


 def test_create_table():
@@ -15,12 +12,13 @@ def test_create_table():
            ret
            == """CREATE TABLE IF NOT EXISTS `category` (
    `id` INT NOT NULL PRIMARY KEY AUTO_INCREMENT,
-    `slug` VARCHAR(200) NOT NULL,
-    `name` VARCHAR(200) NOT NULL,
+    `slug` VARCHAR(100) NOT NULL,
+    `name` VARCHAR(200),
+    `title` VARCHAR(20) NOT NULL,
    `created_at` DATETIME(6) NOT NULL  DEFAULT CURRENT_TIMESTAMP(6),
    `user_id` INT NOT NULL COMMENT 'User',
    CONSTRAINT `fk_category_user_e2e3874c` FOREIGN KEY (`user_id`) REFERENCES `user` (`id`) ON DELETE CASCADE
-) CHARACTER SET utf8mb4;"""
+) CHARACTER SET utf8mb4"""
        )

    elif isinstance(Migrate.ddl, SqliteDDL):
@@ -28,11 +26,12 @@ def test_create_table():
            ret
            == """CREATE TABLE IF NOT EXISTS "category" (
    "id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL,
-    "slug" VARCHAR(200) NOT NULL,
-    "name" VARCHAR(200) NOT NULL,
+    "slug" VARCHAR(100) NOT NULL,
+    "name" VARCHAR(200),
+    "title" VARCHAR(20) NOT NULL,
    "created_at" TIMESTAMP NOT NULL  DEFAULT CURRENT_TIMESTAMP,
    "user_id" INT NOT NULL REFERENCES "user" ("id") ON DELETE CASCADE /* User */
-);"""
+)"""
        )

    elif isinstance(Migrate.ddl, PostgresDDL):
@@ -40,17 +39,18 @@ def test_create_table():
            ret
            == """CREATE TABLE IF NOT EXISTS "category" (
    "id" SERIAL NOT NULL PRIMARY KEY,
-    "slug" VARCHAR(200) NOT NULL,
-    "name" VARCHAR(200) NOT NULL,
+    "slug" VARCHAR(100) NOT NULL,
+    "name" VARCHAR(200),
+    "title" VARCHAR(20) NOT NULL,
    "created_at" TIMESTAMPTZ NOT NULL  DEFAULT CURRENT_TIMESTAMP,
    "user_id" INT NOT NULL REFERENCES "user" ("id") ON DELETE CASCADE
 );
-COMMENT ON COLUMN "category"."user_id" IS 'User';"""
+COMMENT ON COLUMN "category"."user_id" IS 'User'"""
        )


 def test_drop_table():
-    ret = Migrate.ddl.drop_table(Category)
+    ret = Migrate.ddl.drop_table(Category._meta.db_table)
    if isinstance(Migrate.ddl, MysqlDDL):
        assert ret == "DROP TABLE IF EXISTS `category`"
    else:
@@ -58,86 +58,91 @@ def test_drop_table():


 def test_add_column():
-    ret = Migrate.ddl.add_column(Category, Category._meta.fields_map.get("name"))
+    ret = Migrate.ddl.add_column(Category, Category._meta.fields_map.get("name").describe(False))
    if isinstance(Migrate.ddl, MysqlDDL):
-        assert ret == "ALTER TABLE `category` ADD `name` VARCHAR(200) NOT NULL"
+        assert ret == "ALTER TABLE `category` ADD `name` VARCHAR(200)"
    else:
-        assert ret == 'ALTER TABLE "category" ADD "name" VARCHAR(200) NOT NULL'
+        assert ret == 'ALTER TABLE "category" ADD "name" VARCHAR(200)'


 def test_modify_column():
    if isinstance(Migrate.ddl, SqliteDDL):
-        with pytest.raises(NotSupportError):
-            ret0 = Migrate.ddl.modify_column(Category, Category._meta.fields_map.get("name"))
-            ret1 = Migrate.ddl.modify_column(User, User._meta.fields_map.get("is_active"))
-
-    else:
-        ret0 = Migrate.ddl.modify_column(Category, Category._meta.fields_map.get("name"))
-        ret1 = Migrate.ddl.modify_column(User, User._meta.fields_map.get("is_active"))
-    if isinstance(Migrate.ddl, MysqlDDL):
-        assert ret0 == "ALTER TABLE `category` MODIFY COLUMN `name` VARCHAR(200) NOT NULL"
-    elif isinstance(Migrate.ddl, PostgresDDL):
-        assert ret0 == 'ALTER TABLE "category" ALTER COLUMN "name" TYPE VARCHAR(200)'
+        return

+    ret0 = Migrate.ddl.modify_column(
+        Category, Category._meta.fields_map.get("name").describe(False)
+    )
+    ret1 = Migrate.ddl.modify_column(User, User._meta.fields_map.get("is_active").describe(False))
    if isinstance(Migrate.ddl, MysqlDDL):
+        assert ret0 == "ALTER TABLE `category` MODIFY COLUMN `name` VARCHAR(200)"
        assert (
            ret1
            == "ALTER TABLE `user` MODIFY COLUMN `is_active` BOOL NOT NULL  COMMENT 'Is Active' DEFAULT 1"
        )
    elif isinstance(Migrate.ddl, PostgresDDL):
-        assert ret1 == 'ALTER TABLE "user" ALTER COLUMN "is_active" TYPE BOOL'
+        assert (
+            ret0
+            == 'ALTER TABLE "category" ALTER COLUMN "name" TYPE VARCHAR(200) USING "name"::VARCHAR(200)'
+        )
+
+        assert (
+            ret1 == 'ALTER TABLE "user" ALTER COLUMN "is_active" TYPE BOOL USING "is_active"::BOOL'
+        )


 def test_alter_column_default():
-    ret = Migrate.ddl.alter_column_default(Category, Category._meta.fields_map.get("name"))
+    if isinstance(Migrate.ddl, SqliteDDL):
+        return
+    ret = Migrate.ddl.alter_column_default(User, User._meta.fields_map.get("intro").describe(False))
    if isinstance(Migrate.ddl, PostgresDDL):
-        assert ret == 'ALTER TABLE "category" ALTER COLUMN "name" DROP DEFAULT'
-    else:
-        assert ret is None
+        assert ret == 'ALTER TABLE "user" ALTER COLUMN "intro" SET DEFAULT \'\''
+    elif isinstance(Migrate.ddl, MysqlDDL):
+        assert ret == "ALTER TABLE `user` ALTER COLUMN `intro` SET DEFAULT ''"

-    ret = Migrate.ddl.alter_column_default(Category, Category._meta.fields_map.get("created_at"))
+    ret = Migrate.ddl.alter_column_default(
+        Category, Category._meta.fields_map.get("created_at").describe(False)
+    )
    if isinstance(Migrate.ddl, PostgresDDL):
        assert (
            ret == 'ALTER TABLE "category" ALTER COLUMN "created_at" SET DEFAULT CURRENT_TIMESTAMP'
        )
-    else:
-        assert ret is None
+    elif isinstance(Migrate.ddl, MysqlDDL):
+        assert (
+            ret
+            == "ALTER TABLE `category` ALTER COLUMN `created_at` SET DEFAULT CURRENT_TIMESTAMP(6)"
+        )

-    ret = Migrate.ddl.alter_column_default(User, User._meta.fields_map.get("avatar"))
+    ret = Migrate.ddl.alter_column_default(
+        Product, Product._meta.fields_map.get("view_num").describe(False)
+    )
    if isinstance(Migrate.ddl, PostgresDDL):
-        assert ret == 'ALTER TABLE "user" ALTER COLUMN "avatar" SET DEFAULT \'\''
-    else:
-        assert ret is None
+        assert ret == 'ALTER TABLE "product" ALTER COLUMN "view_num" SET DEFAULT 0'
+    elif isinstance(Migrate.ddl, MysqlDDL):
+        assert ret == "ALTER TABLE `product` ALTER COLUMN `view_num` SET DEFAULT 0"


 def test_alter_column_null():
-    ret = Migrate.ddl.alter_column_null(Category, Category._meta.fields_map.get("name"))
+    if isinstance(Migrate.ddl, (SqliteDDL, MysqlDDL)):
+        return
+    ret = Migrate.ddl.alter_column_null(
+        Category, Category._meta.fields_map.get("name").describe(False)
+    )
    if isinstance(Migrate.ddl, PostgresDDL):
-        assert ret == 'ALTER TABLE "category" ALTER COLUMN "name" SET NOT NULL'
-    else:
-        assert ret is None
+        assert ret == 'ALTER TABLE "category" ALTER COLUMN "name" DROP NOT NULL'


 def test_set_comment():
-    ret = Migrate.ddl.set_comment(Category, Category._meta.fields_map.get("name"))
-    if isinstance(Migrate.ddl, PostgresDDL):
-        assert ret == 'COMMENT ON COLUMN "category"."name" IS NULL'
-    else:
-        assert ret is None
+    if isinstance(Migrate.ddl, (SqliteDDL, MysqlDDL)):
+        return
+    ret = Migrate.ddl.set_comment(Category, Category._meta.fields_map.get("name").describe(False))
+    assert ret == 'COMMENT ON COLUMN "category"."name" IS NULL'

-    ret = Migrate.ddl.set_comment(Category, Category._meta.fields_map.get("user"))
-    if isinstance(Migrate.ddl, PostgresDDL):
-        assert ret == 'COMMENT ON COLUMN "category"."user" IS \'User\''
-    else:
-        assert ret is None
+    ret = Migrate.ddl.set_comment(Category, Category._meta.fields_map.get("user").describe(False))
+    assert ret == 'COMMENT ON COLUMN "category"."user_id" IS \'User\''


 def test_drop_column():
-    if isinstance(Migrate.ddl, SqliteDDL):
-        with pytest.raises(NotSupportError):
-            ret = Migrate.ddl.drop_column(Category, "name")
-    else:
-        ret = Migrate.ddl.drop_column(Category, "name")
+    ret = Migrate.ddl.drop_column(Category, "name")
    if isinstance(Migrate.ddl, MysqlDDL):
        assert ret == "ALTER TABLE `category` DROP COLUMN `name`"
    elif isinstance(Migrate.ddl, PostgresDDL):
@@ -148,18 +153,13 @@ def test_add_index():
    index = Migrate.ddl.add_index(Category, ["name"])
    index_u = Migrate.ddl.add_index(Category, ["name"], True)
    if isinstance(Migrate.ddl, MysqlDDL):
-        assert index == "ALTER TABLE `category` ADD  INDEX `idx_category_name_8b0cb9` (`name`)"
-        assert (
-            index_u == "ALTER TABLE `category` ADD UNIQUE INDEX `uid_category_name_8b0cb9` (`name`)"
-        )
+        assert index == "ALTER TABLE `category` ADD INDEX `idx_category_name_8b0cb9` (`name`)"
+        assert index_u == "ALTER TABLE `category` ADD UNIQUE INDEX `name` (`name`)"
    elif isinstance(Migrate.ddl, PostgresDDL):
        assert index == 'CREATE INDEX "idx_category_name_8b0cb9" ON "category" ("name")'
-        assert (
-            index_u
-            == 'ALTER TABLE "category" ADD CONSTRAINT "uid_category_name_8b0cb9" UNIQUE ("name")'
-        )
+        assert index_u == 'CREATE UNIQUE INDEX "uid_category_name_8b0cb9" ON "category" ("name")'
    else:
-        assert index == 'ALTER TABLE "category" ADD  INDEX "idx_category_name_8b0cb9" ("name")'
+        assert index == 'ALTER TABLE "category" ADD INDEX "idx_category_name_8b0cb9" ("name")'
        assert (
            index_u == 'ALTER TABLE "category" ADD UNIQUE INDEX "uid_category_name_8b0cb9" ("name")'
        )
@@ -170,17 +170,19 @@ def test_drop_index():
    ret_u = Migrate.ddl.drop_index(Category, ["name"], True)
    if isinstance(Migrate.ddl, MysqlDDL):
        assert ret == "ALTER TABLE `category` DROP INDEX `idx_category_name_8b0cb9`"
-        assert ret_u == "ALTER TABLE `category` DROP INDEX `uid_category_name_8b0cb9`"
+        assert ret_u == "ALTER TABLE `category` DROP INDEX `name`"
    elif isinstance(Migrate.ddl, PostgresDDL):
        assert ret == 'DROP INDEX "idx_category_name_8b0cb9"'
-        assert ret_u == 'ALTER TABLE "category" DROP CONSTRAINT "uid_category_name_8b0cb9"'
+        assert ret_u == 'DROP INDEX "uid_category_name_8b0cb9"'
    else:
        assert ret == 'ALTER TABLE "category" DROP INDEX "idx_category_name_8b0cb9"'
        assert ret_u == 'ALTER TABLE "category" DROP INDEX "uid_category_name_8b0cb9"'


 def test_add_fk():
-    ret = Migrate.ddl.add_fk(Category, Category._meta.fields_map.get("user"))
+    ret = Migrate.ddl.add_fk(
+        Category, Category._meta.fields_map.get("user").describe(False), User.describe(False)
+    )
    if isinstance(Migrate.ddl, MysqlDDL):
        assert (
            ret
@@ -194,7 +196,9 @@ def test_add_fk():


 def test_drop_fk():
-    ret = Migrate.ddl.drop_fk(Category, Category._meta.fields_map.get("user"))
+    ret = Migrate.ddl.drop_fk(
+        Category, Category._meta.fields_map.get("user").describe(False), User.describe(False)
+    )
    if isinstance(Migrate.ddl, MysqlDDL):
        assert ret == "ALTER TABLE `category` DROP FOREIGN KEY `fk_category_user_e2e3874c`"
    elif isinstance(Migrate.ddl, PostgresDDL):
--- a/tests/test_migrate.py
+++ b/tests/test_migrate.py
--- a/tests/test_utils.py
+++ b/tests/test_utils.py
@@ -0,0 +1,6 @@
+from aerich.utils import import_py_file
+
+
+def test_import_py_file() -> None:
+    m = import_py_file("aerich/utils.py")
+    assert getattr(m, "import_py_file")