diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..3cf8c6d
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+env
+__pycache__
\ No newline at end of file
diff --git a/README.md b/README.md
index 1ce8e16..3465e4d 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,95 @@
-# JieNote_backend
-2025春季软件工程课程团队项目JieNote项目后端
+# JieNote Backend
+
+This is the backend service for JieNote, built with FastAPI.
+
+## Features
+- RESTful API endpoints
+- Modular structure for scalability
+
+## File Structure
+- `app/`: Contains the main application code.
+  - `main.py`: Entry point for the FastAPI application.
+  - `models/`: Database models and schemas.
+  - `core/`: Core configurations and settings.
+    - include database settings
+    - include JWT settings
+    - include CORS settings
+    - ……
+  - `curd/`: CRUD operations for database interactions.
+  - `db/`: Database connection and session management.
+  - `schemas/`: Pydantic schemas for data validation.
+  - `static/`: Static files (e.g., images, CSS).
+  - `routers/`: API route definitions.
+- `tests/`: Contains test cases for the application.
+- `requirements.txt`: List of dependencies.
+- `README.md`: Documentation for the project.
+- `alembic/`: Database migration scripts and configurations.
+- `env/`: Virtual environment (not included in version control).
+- `img/`: Images used in the project.
+
+## Setup
+1. Create a virtual environment: ✔
+   ```bash
+   python -m venv env
+   ```
+2. Activate the virtual environment: 
+   - On Windows:
+     ```bash
+     .\env\Scripts\activate
+     ```
+   - On macOS/Linux:
+     ```bash
+     source env/bin/activate
+     ```
+3. Install dependencies: 
+   ```bash
+   pip install -r requirements.txt
+   ```
+4. freeze requirements(do before commit !!!): 
+   ```bash
+   pip freeze > requirements.txt
+   ```
+
+## Database Migration
+<!-- 数据库迁移使用alembic -->
+1. Install Alembic: ✔
+   ```bash
+   pip install alembic
+   ```
+2. Initialize Alembic: ✔
+   ```bash
+   alembic init alembic
+   ```
+3. Configure Alembic: ✔
+
+   1. Edit `alembic.ini` to set the database URL.
+   2. Edit `alembic/env.py` to set up the target metadata. 
+      ```python
+      from app.models import Base  # Import your models here
+      target_metadata = Base.metadata
+      ```
+4. Create a migration script: need to modify the script
+   ```bash
+   alembic revision --autogenerate -m "提交信息"
+   ```
+5. Apply the migration: need to modify the script
+   ```bash
+   alembic upgrade head
+   ```
+
+
+## Run the Application
+```bash
+uvicorn app.main:app --reload
+```
+
+## Folder Structure
+- `app/`: Contains the main application code.
+- `tests/`: Contains test cases.
+- `env/`: Virtual environment (not included in version control).
+
+## ER Diagram
+![ER Diagram](img/er_diagram.jpg)
+
+## License
+MIT License
diff --git a/alembic.ini b/alembic.ini
new file mode 100644
index 0000000..fa56891
--- /dev/null
+++ b/alembic.ini
@@ -0,0 +1,119 @@
+# A generic, single database configuration.
+
+[alembic]
+# path to migration scripts
+# Use forward slashes (/) also on windows to provide an os agnostic path
+script_location = alembic
+
+# template used to generate migration file names; The default value is %%(rev)s_%%(slug)s
+# Uncomment the line below if you want the files to be prepended with date and time
+# see https://alembic.sqlalchemy.org/en/latest/tutorial.html#editing-the-ini-file
+# for all available tokens
+# file_template = %%(year)d_%%(month).2d_%%(day).2d_%%(hour).2d%%(minute).2d-%%(rev)s_%%(slug)s
+
+# sys.path path, will be prepended to sys.path if present.
+# defaults to the current working directory.
+prepend_sys_path = .
+
+# timezone to use when rendering the date within the migration file
+# as well as the filename.
+# If specified, requires the python>=3.9 or backports.zoneinfo library and tzdata library.
+# Any required deps can installed by adding `alembic[tz]` to the pip requirements
+# string value is passed to ZoneInfo()
+# leave blank for localtime
+# timezone =
+
+# max length of characters to apply to the "slug" field
+# truncate_slug_length = 40
+
+# set to 'true' to run the environment during
+# the 'revision' command, regardless of autogenerate
+# revision_environment = false
+
+# set to 'true' to allow .pyc and .pyo files without
+# a source .py file to be detected as revisions in the
+# versions/ directory
+# sourceless = false
+
+# version location specification; This defaults
+# to alembic/versions.  When using multiple version
+# directories, initial revisions must be specified with --version-path.
+# The path separator used here should be the separator specified by "version_path_separator" below.
+# version_locations = %(here)s/bar:%(here)s/bat:alembic/versions
+
+# version path separator; As mentioned above, this is the character used to split
+# version_locations. The default within new alembic.ini files is "os", which uses os.pathsep.
+# If this key is omitted entirely, it falls back to the legacy behavior of splitting on spaces and/or commas.
+# Valid values for version_path_separator are:
+#
+# version_path_separator = :
+# version_path_separator = ;
+# version_path_separator = space
+# version_path_separator = newline
+#
+# Use os.pathsep. Default configuration used for new projects.
+version_path_separator = os
+
+# set to 'true' to search source files recursively
+# in each "version_locations" directory
+# new in Alembic version 1.10
+# recursive_version_locations = false
+
+# the output encoding used when revision files
+# are written from script.py.mako
+# output_encoding = utf-8
+
+sqlalchemy.url = mysql+pymysql://root:coders007@47.93.172.156:3306/JieNote
+
+
+[post_write_hooks]
+# post_write_hooks defines scripts or Python functions that are run
+# on newly generated revision scripts.  See the documentation for further
+# detail and examples
+
+# format using "black" - use the console_scripts runner, against the "black" entrypoint
+# hooks = black
+# black.type = console_scripts
+# black.entrypoint = black
+# black.options = -l 79 REVISION_SCRIPT_FILENAME
+
+# lint with attempts to fix using "ruff" - use the exec runner, execute a binary
+# hooks = ruff
+# ruff.type = exec
+# ruff.executable = %(here)s/.venv/bin/ruff
+# ruff.options = check --fix REVISION_SCRIPT_FILENAME
+
+# Logging configuration
+[loggers]
+keys = root,sqlalchemy,alembic
+
+[handlers]
+keys = console
+
+[formatters]
+keys = generic
+
+[logger_root]
+level = WARNING
+handlers = console
+qualname =
+
+[logger_sqlalchemy]
+level = WARNING
+handlers =
+qualname = sqlalchemy.engine
+
+[logger_alembic]
+level = INFO
+handlers =
+qualname = alembic
+
+[handler_console]
+class = StreamHandler
+args = (sys.stderr,)
+level = NOTSET
+formatter = generic
+
+[formatter_generic]
+format = %(levelname)-5.5s [%(name)s] %(message)s
+datefmt = %H:%M:%S
diff --git a/alembic/README b/alembic/README
new file mode 100644
index 0000000..98e4f9c
--- /dev/null
+++ b/alembic/README
@@ -0,0 +1 @@
+Generic single-database configuration.
\ No newline at end of file
diff --git a/alembic/env.py b/alembic/env.py
new file mode 100644
index 0000000..41ef15e
--- /dev/null
+++ b/alembic/env.py
@@ -0,0 +1,79 @@
+from logging.config import fileConfig
+
+from sqlalchemy import engine_from_config
+from sqlalchemy import pool
+from app.db.base import Base
+
+from alembic import context
+
+# this is the Alembic Config object, which provides
+# access to the values within the .ini file in use.
+config = context.config
+
+# Interpret the config file for Python logging.
+# This line sets up loggers basically.
+if config.config_file_name is not None:
+    fileConfig(config.config_file_name)
+
+# add your model's MetaData object here
+# for 'autogenerate' support
+# from myapp import mymodel
+# target_metadata = mymodel.Base.metadata
+target_metadata = Base.metadata
+
+# other values from the config, defined by the needs of env.py,
+# can be acquired:
+# my_important_option = config.get_main_option("my_important_option")
+# ... etc.
+
+
+def run_migrations_offline() -> None:
+    """Run migrations in 'offline' mode.
+
+    This configures the context with just a URL
+    and not an Engine, though an Engine is acceptable
+    here as well.  By skipping the Engine creation
+    we don't even need a DBAPI to be available.
+
+    Calls to context.execute() here emit the given string to the
+    script output.
+
+    """
+    url = config.get_main_option("sqlalchemy.url")
+    context.configure(
+        url=url,
+        target_metadata=target_metadata,
+        literal_binds=True,
+        dialect_opts={"paramstyle": "named"},
+    )
+
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+def run_migrations_online() -> None:
+    """Run migrations in 'online' mode.
+
+    In this scenario we need to create an Engine
+    and associate a connection with the context.
+
+    """
+    connectable = engine_from_config(
+        config.get_section(config.config_ini_section, {}),
+        prefix="sqlalchemy.",
+        poolclass=pool.NullPool,
+    )
+
+    with connectable.connect() as connection:
+        context.configure(
+            connection=connection, target_metadata=target_metadata
+        )
+
+        with context.begin_transaction():
+            context.run_migrations()
+
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    run_migrations_online()
diff --git a/alembic/script.py.mako b/alembic/script.py.mako
new file mode 100644
index 0000000..480b130
--- /dev/null
+++ b/alembic/script.py.mako
@@ -0,0 +1,28 @@
+"""${message}
+
+Revision ID: ${up_revision}
+Revises: ${down_revision | comma,n}
+Create Date: ${create_date}
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+${imports if imports else ""}
+
+# revision identifiers, used by Alembic.
+revision: str = ${repr(up_revision)}
+down_revision: Union[str, None] = ${repr(down_revision)}
+branch_labels: Union[str, Sequence[str], None] = ${repr(branch_labels)}
+depends_on: Union[str, Sequence[str], None] = ${repr(depends_on)}
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    ${upgrades if upgrades else "pass"}
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    ${downgrades if downgrades else "pass"}
diff --git a/alembic/versions/1bf7c40393d4_definition_of_all_entity_and_relation.py b/alembic/versions/1bf7c40393d4_definition_of_all_entity_and_relation.py
new file mode 100644
index 0000000..8c6e9f2
--- /dev/null
+++ b/alembic/versions/1bf7c40393d4_definition_of_all_entity_and_relation.py
@@ -0,0 +1,77 @@
+"""definition of all entity and relation
+
+Revision ID: 1bf7c40393d4
+Revises: 56ae02842433
+Create Date: 2025-04-10 10:44:24.487467
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision: str = '1bf7c40393d4'
+down_revision: Union[str, None] = '56ae02842433'
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.create_table('articlenotes',
+    sa.Column('articleid', sa.Integer(), nullable=True),
+    sa.Column('noteid', sa.Integer(), nullable=False),
+    sa.PrimaryKeyConstraint('noteid')
+    )
+    op.create_index(op.f('ix_articlenotes_noteid'), 'articlenotes', ['noteid'], unique=False)
+    op.create_table('articlesetarticles',
+    sa.Column('articlesetid', sa.Integer(), nullable=True),
+    sa.Column('articleid', sa.Integer(), nullable=False),
+    sa.PrimaryKeyConstraint('articleid')
+    )
+    op.create_index(op.f('ix_articlesetarticles_articleid'), 'articlesetarticles', ['articleid'], unique=False)
+    op.create_table('articletags',
+    sa.Column('articleid', sa.Integer(), nullable=True),
+    sa.Column('tagid', sa.Integer(), nullable=False),
+    sa.PrimaryKeyConstraint('tagid')
+    )
+    op.create_index(op.f('ix_articletags_tagid'), 'articletags', ['tagid'], unique=False)
+    op.create_table('grouparticlesets',
+    sa.Column('groupid', sa.Integer(), nullable=True),
+    sa.Column('articlesetid', sa.Integer(), nullable=False),
+    sa.PrimaryKeyConstraint('articlesetid')
+    )
+    op.create_index(op.f('ix_grouparticlesets_articlesetid'), 'grouparticlesets', ['articlesetid'], unique=False)
+    op.create_table('userarticlesets',
+    sa.Column('userid', sa.Integer(), nullable=True),
+    sa.Column('articlesetid', sa.Integer(), nullable=False),
+    sa.PrimaryKeyConstraint('articlesetid')
+    )
+    op.create_index(op.f('ix_userarticlesets_articlesetid'), 'userarticlesets', ['articlesetid'], unique=False)
+    op.create_table('usergroups',
+    sa.Column('userid', sa.Integer(), nullable=False),
+    sa.Column('groupid', sa.Integer(), nullable=False),
+    sa.Column('isadmin', sa.Boolean(), nullable=True),
+    sa.PrimaryKeyConstraint('userid', 'groupid')
+    )
+    # ### end Alembic commands ###
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_table('usergroups')
+    op.drop_index(op.f('ix_userarticlesets_articlesetid'), table_name='userarticlesets')
+    op.drop_table('userarticlesets')
+    op.drop_index(op.f('ix_grouparticlesets_articlesetid'), table_name='grouparticlesets')
+    op.drop_table('grouparticlesets')
+    op.drop_index(op.f('ix_articletags_tagid'), table_name='articletags')
+    op.drop_table('articletags')
+    op.drop_index(op.f('ix_articlesetarticles_articleid'), table_name='articlesetarticles')
+    op.drop_table('articlesetarticles')
+    op.drop_index(op.f('ix_articlenotes_noteid'), table_name='articlenotes')
+    op.drop_table('articlenotes')
+    # ### end Alembic commands ###
diff --git a/alembic/versions/56ae02842433_definition_of_all_entity.py b/alembic/versions/56ae02842433_definition_of_all_entity.py
new file mode 100644
index 0000000..0cf41da
--- /dev/null
+++ b/alembic/versions/56ae02842433_definition_of_all_entity.py
@@ -0,0 +1,46 @@
+"""definition of all entity
+
+Revision ID: 56ae02842433
+Revises: c976ca5c1d8f
+Create Date: 2025-04-10 00:04:27.588283
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+from sqlalchemy.dialects import mysql
+
+# revision identifiers, used by Alembic.
+revision: str = '56ae02842433'
+down_revision: Union[str, None] = 'c976ca5c1d8f'
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.add_column('users', sa.Column('email', sa.String(length=30), nullable=False))
+    op.add_column('users', sa.Column('username', sa.String(length=30), nullable=False))
+    op.drop_index('ix_users_teacher_name', table_name='users')
+    op.drop_index('ix_users_work_number', table_name='users')
+    op.create_index(op.f('ix_users_email'), 'users', ['email'], unique=True)
+    op.create_index(op.f('ix_users_username'), 'users', ['username'], unique=False)
+    op.drop_column('users', 'teacher_name')
+    op.drop_column('users', 'work_number')
+    # ### end Alembic commands ###
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.add_column('users', sa.Column('work_number', mysql.INTEGER(), autoincrement=False, nullable=False))
+    op.add_column('users', sa.Column('teacher_name', mysql.VARCHAR(length=20), nullable=False))
+    op.drop_index(op.f('ix_users_username'), table_name='users')
+    op.drop_index(op.f('ix_users_email'), table_name='users')
+    op.create_index('ix_users_work_number', 'users', ['work_number'], unique=False)
+    op.create_index('ix_users_teacher_name', 'users', ['teacher_name'], unique=False)
+    op.drop_column('users', 'username')
+    op.drop_column('users', 'email')
+    # ### end Alembic commands ###
diff --git a/alembic/versions/5c562ce917d3_init.py b/alembic/versions/5c562ce917d3_init.py
new file mode 100644
index 0000000..da6aaf7
--- /dev/null
+++ b/alembic/versions/5c562ce917d3_init.py
@@ -0,0 +1,44 @@
+"""init
+
+Revision ID: 5c562ce917d3
+Revises: e911f584a9c0
+Create Date: 2025-04-09 10:20:46.223969
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision: str = '5c562ce917d3'
+down_revision: Union[str, None] = 'e911f584a9c0'
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.create_table('users',
+    sa.Column('id', sa.Integer(), autoincrement=True, nullable=False),
+    sa.Column('work_number', sa.Integer(), nullable=False),
+    sa.Column('hash_password', sa.String(length=60), nullable=False),
+    sa.Column('teacher_name', sa.String(length=20), nullable=False),
+    sa.PrimaryKeyConstraint('id')
+    )
+    op.create_index(op.f('ix_users_id'), 'users', ['id'], unique=False)
+    op.create_index(op.f('ix_users_teacher_name'), 'users', ['teacher_name'], unique=False)
+    op.create_index(op.f('ix_users_work_number'), 'users', ['work_number'], unique=False)
+    # ### end Alembic commands ###
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_index(op.f('ix_users_work_number'), table_name='users')
+    op.drop_index(op.f('ix_users_teacher_name'), table_name='users')
+    op.drop_index(op.f('ix_users_id'), table_name='users')
+    op.drop_table('users')
+    # ### end Alembic commands ###
diff --git "a/alembic/versions/5dc79cf05715_\346\267\273\345\212\240\346\225\260\346\215\256\345\272\223\345\256\236\344\275\223\345\205\263\347\263\273\345\256\232\344\271\211.py" "b/alembic/versions/5dc79cf05715_\346\267\273\345\212\240\346\225\260\346\215\256\345\272\223\345\256\236\344\275\223\345\205\263\347\263\273\345\256\232\344\271\211.py"
new file mode 100644
index 0000000..cacd6d0
--- /dev/null
+++ "b/alembic/versions/5dc79cf05715_\346\267\273\345\212\240\346\225\260\346\215\256\345\272\223\345\256\236\344\275\223\345\205\263\347\263\273\345\256\232\344\271\211.py"
@@ -0,0 +1,141 @@
+"""添加数据库实体关系定义
+
+Revision ID: 5dc79cf05715
+Revises: 1bf7c40393d4
+Create Date: 2025-04-11 20:59:07.250741
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+from sqlalchemy.dialects import mysql
+
+# revision identifiers, used by Alembic.
+revision: str = '5dc79cf05715'
+down_revision: Union[str, None] = '1bf7c40393d4'
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.create_table('folders',
+    sa.Column('id', sa.Integer(), autoincrement=True, nullable=False),
+    sa.Column('name', sa.String(length=30), nullable=True),
+    sa.Column('user_id', sa.Integer(), nullable=True),
+    sa.Column('groups_id', sa.Integer(), nullable=True),
+    sa.ForeignKeyConstraint(['groups_id'], ['groups.id'], ),
+    sa.ForeignKeyConstraint(['user_id'], ['users.id'], ),
+    sa.PrimaryKeyConstraint('id')
+    )
+    op.create_index(op.f('ix_folders_id'), 'folders', ['id'], unique=False)
+    op.create_table('user_group',
+    sa.Column('user_id', sa.Integer(), nullable=False),
+    sa.Column('group_id', sa.Integer(), nullable=False),
+    sa.Column('is_admin', sa.Boolean(), nullable=True),
+    sa.ForeignKeyConstraint(['group_id'], ['groups.id'], ),
+    sa.ForeignKeyConstraint(['user_id'], ['users.id'], ),
+    sa.PrimaryKeyConstraint('user_id', 'group_id')
+    )
+    op.drop_index('ix_articlesetarticles_articleid', table_name='articlesetarticles')
+    op.drop_table('articlesetarticles')
+    op.drop_index('ix_articletags_tagid', table_name='articletags')
+    op.drop_table('articletags')
+    op.drop_index('ix_userarticlesets_articlesetid', table_name='userarticlesets')
+    op.drop_table('userarticlesets')
+    op.drop_index('ix_grouparticlesets_articlesetid', table_name='grouparticlesets')
+    op.drop_table('grouparticlesets')
+    op.drop_index('ix_articlesets_id', table_name='articlesets')
+    op.drop_table('articlesets')
+    op.drop_index('ix_articlenotes_noteid', table_name='articlenotes')
+    op.drop_table('articlenotes')
+    op.drop_table('usergroups')
+    op.add_column('articles', sa.Column('folder_id', sa.Integer(), nullable=True))
+    op.create_foreign_key(None, 'articles', 'folders', ['folder_id'], ['id'])
+    op.add_column('notes', sa.Column('article_id', sa.Integer(), nullable=True))
+    op.create_foreign_key(None, 'notes', 'articles', ['article_id'], ['id'])
+    op.add_column('tags', sa.Column('article_id', sa.Integer(), nullable=True))
+    op.create_foreign_key(None, 'tags', 'articles', ['article_id'], ['id'])
+    op.add_column('users', sa.Column('avatar', sa.String(length=100), nullable=True))
+    # ### end Alembic commands ###
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_column('users', 'avatar')
+    op.drop_constraint(None, 'tags', type_='foreignkey')
+    op.drop_column('tags', 'article_id')
+    op.drop_constraint(None, 'notes', type_='foreignkey')
+    op.drop_column('notes', 'article_id')
+    op.drop_constraint(None, 'articles', type_='foreignkey')
+    op.drop_column('articles', 'folder_id')
+    op.create_table('usergroups',
+    sa.Column('userid', mysql.INTEGER(), autoincrement=False, nullable=False),
+    sa.Column('groupid', mysql.INTEGER(), autoincrement=False, nullable=False),
+    sa.Column('isadmin', mysql.TINYINT(display_width=1), autoincrement=False, nullable=True),
+    sa.PrimaryKeyConstraint('userid', 'groupid'),
+    mysql_collate='utf8mb4_0900_ai_ci',
+    mysql_default_charset='utf8mb4',
+    mysql_engine='InnoDB'
+    )
+    op.create_table('articlenotes',
+    sa.Column('articleid', mysql.INTEGER(), autoincrement=False, nullable=True),
+    sa.Column('noteid', mysql.INTEGER(), autoincrement=True, nullable=False),
+    sa.PrimaryKeyConstraint('noteid'),
+    mysql_collate='utf8mb4_0900_ai_ci',
+    mysql_default_charset='utf8mb4',
+    mysql_engine='InnoDB'
+    )
+    op.create_index('ix_articlenotes_noteid', 'articlenotes', ['noteid'], unique=False)
+    op.create_table('articlesets',
+    sa.Column('id', mysql.INTEGER(), autoincrement=True, nullable=False),
+    sa.Column('name', mysql.VARCHAR(length=30), nullable=True),
+    sa.PrimaryKeyConstraint('id'),
+    mysql_collate='utf8mb4_0900_ai_ci',
+    mysql_default_charset='utf8mb4',
+    mysql_engine='InnoDB'
+    )
+    op.create_index('ix_articlesets_id', 'articlesets', ['id'], unique=False)
+    op.create_table('grouparticlesets',
+    sa.Column('groupid', mysql.INTEGER(), autoincrement=False, nullable=True),
+    sa.Column('articlesetid', mysql.INTEGER(), autoincrement=True, nullable=False),
+    sa.PrimaryKeyConstraint('articlesetid'),
+    mysql_collate='utf8mb4_0900_ai_ci',
+    mysql_default_charset='utf8mb4',
+    mysql_engine='InnoDB'
+    )
+    op.create_index('ix_grouparticlesets_articlesetid', 'grouparticlesets', ['articlesetid'], unique=False)
+    op.create_table('userarticlesets',
+    sa.Column('userid', mysql.INTEGER(), autoincrement=False, nullable=True),
+    sa.Column('articlesetid', mysql.INTEGER(), autoincrement=True, nullable=False),
+    sa.PrimaryKeyConstraint('articlesetid'),
+    mysql_collate='utf8mb4_0900_ai_ci',
+    mysql_default_charset='utf8mb4',
+    mysql_engine='InnoDB'
+    )
+    op.create_index('ix_userarticlesets_articlesetid', 'userarticlesets', ['articlesetid'], unique=False)
+    op.create_table('articletags',
+    sa.Column('articleid', mysql.INTEGER(), autoincrement=False, nullable=True),
+    sa.Column('tagid', mysql.INTEGER(), autoincrement=True, nullable=False),
+    sa.PrimaryKeyConstraint('tagid'),
+    mysql_collate='utf8mb4_0900_ai_ci',
+    mysql_default_charset='utf8mb4',
+    mysql_engine='InnoDB'
+    )
+    op.create_index('ix_articletags_tagid', 'articletags', ['tagid'], unique=False)
+    op.create_table('articlesetarticles',
+    sa.Column('articlesetid', mysql.INTEGER(), autoincrement=False, nullable=True),
+    sa.Column('articleid', mysql.INTEGER(), autoincrement=True, nullable=False),
+    sa.PrimaryKeyConstraint('articleid'),
+    mysql_collate='utf8mb4_0900_ai_ci',
+    mysql_default_charset='utf8mb4',
+    mysql_engine='InnoDB'
+    )
+    op.create_index('ix_articlesetarticles_articleid', 'articlesetarticles', ['articleid'], unique=False)
+    op.drop_table('user_group')
+    op.drop_index(op.f('ix_folders_id'), table_name='folders')
+    op.drop_table('folders')
+    # ### end Alembic commands ###
diff --git "a/alembic/versions/b7940480e6e6_\346\267\273\345\212\240\346\225\260\346\215\256\345\272\223\345\256\236\344\275\223\345\205\263\347\263\273\345\256\232\344\271\211.py" "b/alembic/versions/b7940480e6e6_\346\267\273\345\212\240\346\225\260\346\215\256\345\272\223\345\256\236\344\275\223\345\205\263\347\263\273\345\256\232\344\271\211.py"
new file mode 100644
index 0000000..1b082cb
--- /dev/null
+++ "b/alembic/versions/b7940480e6e6_\346\267\273\345\212\240\346\225\260\346\215\256\345\272\223\345\256\236\344\275\223\345\205\263\347\263\273\345\256\232\344\271\211.py"
@@ -0,0 +1,40 @@
+"""添加数据库实体关系定义
+
+Revision ID: b7940480e6e6
+Revises: 5dc79cf05715
+Create Date: 2025-04-11 21:10:47.613089
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+from sqlalchemy.dialects import mysql
+
+# revision identifiers, used by Alembic.
+revision: str = 'b7940480e6e6'
+down_revision: Union[str, None] = '5dc79cf05715'
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.add_column('folders', sa.Column('group_id', sa.Integer(), nullable=True))
+    op.create_unique_constraint('uq_user_group_folder', 'folders', ['user_id', 'group_id'])
+    op.drop_constraint('folders_ibfk_1', 'folders', type_='foreignkey')
+    op.create_foreign_key(None, 'folders', 'groups', ['group_id'], ['id'])
+    op.drop_column('folders', 'groups_id')
+    # ### end Alembic commands ###
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.add_column('folders', sa.Column('groups_id', mysql.INTEGER(), autoincrement=False, nullable=True))
+    op.drop_constraint(None, 'folders', type_='foreignkey')
+    op.create_foreign_key('folders_ibfk_1', 'folders', 'groups', ['groups_id'], ['id'])
+    op.drop_constraint('uq_user_group_folder', 'folders', type_='unique')
+    op.drop_column('folders', 'group_id')
+    # ### end Alembic commands ###
diff --git "a/alembic/versions/c976ca5c1d8f_\344\275\277\347\224\250\350\277\234\347\250\213\346\225\260\346\215\256\345\272\223.py" "b/alembic/versions/c976ca5c1d8f_\344\275\277\347\224\250\350\277\234\347\250\213\346\225\260\346\215\256\345\272\223.py"
new file mode 100644
index 0000000..f27967b
--- /dev/null
+++ "b/alembic/versions/c976ca5c1d8f_\344\275\277\347\224\250\350\277\234\347\250\213\346\225\260\346\215\256\345\272\223.py"
@@ -0,0 +1,44 @@
+"""使用远程数据库
+
+Revision ID: c976ca5c1d8f
+Revises: 5c562ce917d3
+Create Date: 2025-04-09 21:33:43.133516
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision: str = 'c976ca5c1d8f'
+down_revision: Union[str, None] = '5c562ce917d3'
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.create_table('users',
+    sa.Column('id', sa.Integer(), autoincrement=True, nullable=False),
+    sa.Column('work_number', sa.Integer(), nullable=False),
+    sa.Column('hash_password', sa.String(length=60), nullable=False),
+    sa.Column('teacher_name', sa.String(length=20), nullable=False),
+    sa.PrimaryKeyConstraint('id')
+    )
+    op.create_index(op.f('ix_users_id'), 'users', ['id'], unique=False)
+    op.create_index(op.f('ix_users_teacher_name'), 'users', ['teacher_name'], unique=False)
+    op.create_index(op.f('ix_users_work_number'), 'users', ['work_number'], unique=False)
+    # ### end Alembic commands ###
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_index(op.f('ix_users_work_number'), table_name='users')
+    op.drop_index(op.f('ix_users_teacher_name'), table_name='users')
+    op.drop_index(op.f('ix_users_id'), table_name='users')
+    op.drop_table('users')
+    # ### end Alembic commands ###
diff --git a/alembic/versions/e911f584a9c0_init.py b/alembic/versions/e911f584a9c0_init.py
new file mode 100644
index 0000000..9114c37
--- /dev/null
+++ b/alembic/versions/e911f584a9c0_init.py
@@ -0,0 +1,42 @@
+"""init
+
+Revision ID: e911f584a9c0
+Revises: 
+Create Date: 2025-04-09 10:17:37.889061
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+from sqlalchemy.dialects import mysql
+
+# revision identifiers, used by Alembic.
+revision: str = 'e911f584a9c0'
+down_revision: Union[str, None] = None
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_index('ix_examples_id', table_name='examples')
+    op.drop_table('examples')
+    # ### end Alembic commands ###
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.create_table('examples',
+    sa.Column('id', mysql.INTEGER(), autoincrement=True, nullable=False),
+    sa.Column('name', mysql.VARCHAR(length=50), nullable=False),
+    sa.Column('description', mysql.VARCHAR(length=255), nullable=True),
+    sa.PrimaryKeyConstraint('id'),
+    mysql_collate='utf8mb4_0900_ai_ci',
+    mysql_default_charset='utf8mb4',
+    mysql_engine='InnoDB'
+    )
+    op.create_index('ix_examples_id', 'examples', ['id'], unique=False)
+    # ### end Alembic commands ###
diff --git a/app/__init__.py b/app/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/app/api/__init__.py b/app/api/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/app/api/v1/__init__.py b/app/api/v1/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/app/api/v1/endpoints/__init__.py b/app/api/v1/endpoints/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/app/core/__init__.py b/app/core/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/app/core/config.py b/app/core/config.py
new file mode 100644
index 0000000..68818c4
--- /dev/null
+++ b/app/core/config.py
@@ -0,0 +1,6 @@
+class Settings:
+    PROJECT_NAME: str = "JieNote Backend"
+    VERSION: str = "1.0.0"
+    SQLALCHEMY_DATABASE_URL = "mysql+pymysql://root:coders007@47.93.172.156:3306/JieNote"  # 替换为实际的用户名、密码和数据库名称
+
+settings = Settings()
\ No newline at end of file
diff --git a/app/curd/__init__.py b/app/curd/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/app/db/base.py b/app/db/base.py
new file mode 100644
index 0000000..d885a92
--- /dev/null
+++ b/app/db/base.py
@@ -0,0 +1,2 @@
+from app.db.base_class import Base  # 导入创建的base类
+from app.models.model import User
\ No newline at end of file
diff --git a/app/db/base_class.py b/app/db/base_class.py
new file mode 100644
index 0000000..d692f60
--- /dev/null
+++ b/app/db/base_class.py
@@ -0,0 +1,13 @@
+from typing import Any
+
+from sqlalchemy.ext.declarative import as_declarative, declared_attr
+
+
+@as_declarative()
+class Base:
+    id: Any
+    __name__: str
+    # Generate __tablename__ automatically
+    @declared_attr
+    def __tablename__(cls) -> str:
+        return cls.__name__.lower()
\ No newline at end of file
diff --git a/app/db/session.py b/app/db/session.py
new file mode 100644
index 0000000..5801d8e
--- /dev/null
+++ b/app/db/session.py
@@ -0,0 +1,7 @@
+from sqlalchemy import create_engine
+from sqlalchemy.orm import sessionmaker
+
+from app.core.config import settings
+
+engine = create_engine(settings.SQLALCHEMY_DATABASE_URI, pool_pre_ping=True)    #连接mysql
+SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)  
\ No newline at end of file
diff --git a/app/main.py b/app/main.py
new file mode 100644
index 0000000..e8f2e2f
--- /dev/null
+++ b/app/main.py
@@ -0,0 +1,11 @@
+from fastapi import FastAPI
+
+app = FastAPI()
+
+@app.get("/")
+def read_root():
+    return {"Hello": "World"}
+
+@app.get("/items/{item_id}")
+def read_item(item_id: int, q: str = None):
+    return {"item_id": item_id, "q": q}
\ No newline at end of file
diff --git a/app/models/__init__.py b/app/models/__init__.py
new file mode 100644
index 0000000..026426c
--- /dev/null
+++ b/app/models/__init__.py
@@ -0,0 +1 @@
+from .model import User
\ No newline at end of file
diff --git a/app/models/base.py b/app/models/base.py
new file mode 100644
index 0000000..860e542
--- /dev/null
+++ b/app/models/base.py
@@ -0,0 +1,3 @@
+from sqlalchemy.ext.declarative import declarative_base
+
+Base = declarative_base()
diff --git a/app/models/model.py b/app/models/model.py
new file mode 100644
index 0000000..0f2959d
--- /dev/null
+++ b/app/models/model.py
@@ -0,0 +1,76 @@
+from sqlalchemy import Column, Integer, String, Boolean, Table, ForeignKey, UniqueConstraint
+from sqlalchemy.orm import relationship
+
+from app.db.base_class import Base
+
+# 多对多关系表
+user_group = Table(
+    'user_group', Base.metadata,
+    Column('user_id', Integer, ForeignKey('users.id'), primary_key=True),
+    Column('group_id', Integer, ForeignKey('groups.id'), primary_key=True),
+    Column('is_admin', Boolean, default=False)  # 是否是管理员
+)
+
+class User(Base):
+    __tablename__ = 'users'
+
+    id = Column(Integer, primary_key=True, index=True, autoincrement=True)
+    email = Column(String(30), index=True, nullable=False, unique=True)
+    username = Column(String(30), index=True, nullable=False)
+    hash_password = Column(String(60), nullable=False)
+    avatar = Column(String(100), nullable=True)  # 头像的url
+    groups = relationship('Group', secondary=user_group, back_populates='users')
+
+class Group(Base):
+    __tablename__ = 'groups'
+
+    id = Column(Integer, primary_key=True, index=True, autoincrement=True)
+    leader = Column(Integer)    # the id of the leader
+    users = relationship('User', secondary=user_group, back_populates='groups')
+
+class Folder(Base): # 文件夹
+    __tablename__ = 'folders'
+
+    id = Column(Integer, primary_key=True, index=True, autoincrement=True)
+    name = Column(String(30))
+    user_id = Column(Integer, ForeignKey('users.id'))
+    group_id = Column(Integer, ForeignKey('groups.id'))
+    user = relationship('User', back_populates='folders')
+    group = relationship('Group', back_populates='folders')
+
+    __table_args__ = (
+        UniqueConstraint('user_id', 'group_id', name='uq_user_group_folder'),
+    )
+
+class Article(Base):
+    __tablename__ = 'articles'
+
+    id = Column(Integer, primary_key=True, index=True, autoincrement=True)
+    name = Column(String(30))
+    folder_id = Column(Integer, ForeignKey('folders.id'))
+    folder = relationship('Folder', back_populates='articles')
+
+class Note(Base):
+    __tablename__ = 'notes'
+
+    id = Column(Integer, primary_key=True, index=True, autoincrement=True)
+    name = Column(String(30))
+    article_id = Column(Integer, ForeignKey('articles.id'))
+    article = relationship('Article', back_populates='notes')
+
+class Tag(Base):
+    __tablename__ = 'tags'
+
+    id = Column(Integer, primary_key=True, index=True, autoincrement=True)
+    content = Column(String(30))
+    article_id = Column(Integer, ForeignKey('articles.id'))
+    article = relationship('Article', back_populates='tags')
+
+# 添加反向关系
+User.folders = relationship('Folder', back_populates='users')
+Group.folders = relationship('Folder', back_populates='groups')
+Folder.articles = relationship('Article', back_populates='folders')
+Article.notes = relationship('Note', back_populates='articles')
+Article.tags = relationship('Tag', back_populates='articles')
+
+
diff --git a/app/routers/__init__.py b/app/routers/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/app/schemas/__init__.py b/app/schemas/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/app/static/__init__.py b/app/static/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/img/er_diagram.jpg b/img/er_diagram.jpg
new file mode 100644
index 0000000..fd353ee
Binary files /dev/null and b/img/er_diagram.jpg differ
diff --git a/requirements.txt b/requirements.txt
new file mode 100644
index 0000000..84b9803
--- /dev/null
+++ b/requirements.txt
@@ -0,0 +1,23 @@
+alembic==1.15.2
+annotated-types==0.7.0
+anyio==4.9.0
+click==8.1.8
+colorama==0.4.6
+dotenv==0.9.9
+fastapi==0.115.12
+greenlet==3.1.1
+h11==0.14.0
+idna==3.10
+Mako==1.3.9
+MarkupSafe==3.0.2
+passlib==1.7.4
+pydantic==2.11.2
+pydantic_core==2.33.1
+PyMySQL==1.1.1
+python-dotenv==1.1.0
+sniffio==1.3.1
+SQLAlchemy==2.0.40
+starlette==0.46.1
+typing-inspection==0.4.0
+typing_extensions==4.13.1
+uvicorn==0.34.0
diff --git a/tests/__init__.py b/tests/__init__.py
new file mode 100644
index 0000000..e69de29