# 更新Homebrew确保获取最新版本
brew update

# 安装MySQL服务器
brew install mysql

# 启动MySQL服务
brew services start mysql

# 检查服务状态
brew services list | grep mysql

# 运行安全安装脚本
mysql_secure_installation

# 连接到MySQL服务器
mysql -u root -p

# MySQL命令行中执行简单查询验证安装成功
SHOW DATABASES;
exit;

mysql -u root -p

-- SQL命令开始 --
CREATE DATABASE langchain_db CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;

CREATE USER 'langchain_user'@'localhost' IDENTIFIED BY 'your_secure_password';

GRANT ALL PRIVILEGES ON langchain_db.* TO 'langchain_user'@'localhost';

FLUSH PRIVILEGES;
-- SQL命令结束 --

exit;

# M1/M2芯片推荐使用conda管理Python环境以避免兼容性问题
brew install --cask miniconda

# conda初始化（根据提示操作）
conda init "$(basename "${SHELL}")"

# 重启终端后创建Python环境
conda create -n langchain python=3.9 -y
conda activate langchain

pip install langchain openai mysql-connector-python python-dotenv sqlalchemy pymysql tiktoken

import os
from dotenv import load_dotenv
from langchain import OpenAI, SQLDatabase, SQLDatabaseChain

# Load environment variables from .env file (create one if not exists)
load_dotenv()

# Database configuration - store these in your .env file in real projects!
DB_USER = "langchain_user"
DB_PASSWORD = "your_secure_password" # Replace with your actual password!
DB_HOST = "localhost"
DB_NAME = "langchain_db"

# Initialize database connection using SQLAlchemy for better compatibility with LangChain
db = SQLDatabase.from_uri(
    f"mysql+pymysql://{DB_USER}:{DB_PASSWORD}@{DB_HOST}/{DB_NAME}",
    include_tables=['your_table_name'], # Optional: specify tables to include for security/speed 
    sample_rows_in_table_info=3 # Show sample rows in table description (helps LLM understand schema)
)

# Initialize LLM (OpenAI example - you can replace with other LLMs supported by LangChain)
llm = OpenAI(temperature=0, model_name="gpt-3.5-turbo") 

# Create database chain that combines LLM and database access capabilities 
db_chain = SQLDatabaseChain.from_llm(llm, db, verbose=True)

try:
    # Test simple query to verify connection and basic functionality works

    # First create a test table (for demo purposes only)
    db.run("CREATE TABLE IF NOT EXISTS test_table (id INT AUTO_INCREMENT PRIMARY KEY, name VARCHAR(255), description TEXT);")

    # Insert some test data if table is empty (for demo purposes only)
    if db.run("SELECT COUNT(*) FROM test_table;")[0][0] == '0':
        db.run("INSERT INTO test_table (name, description) VALUES ('Sample Item', 'This is a test item for LangChain demo');")

    # Ask a natural language question that requires database access to answer 
    question = "What is the description of the item named 'Sample Item'?"

    print(f"\nQuestion: {question}")
    answer = db_chain.run(question)
    print(f"\nAnswer: {answer}")

except Exception as e:
    print(f"Error occurred: {str(e)}")
finally:
    # Clean up demo table (optional)
    db.run("DROP TABLE IF EXISTS test_table;")

OPENAI_API_KEY=your_openai_api_key_here # Required if using OpenAI models 
DB_USER=langchain_user                  # Match your MySQL user credentials 
DB_PASSWORD=your_secure_password        # Match your MySQL password  
DB_HOST=localhost                       # Typically localhost unless remote DB  
DB_NAME=langchain_db                    # The database we created earlier  

# Check if MySQL service is running  
brew services list  

# If not running, start it  
brew services start mysql  

# Verify socket location  
mysqladmin variables | grep socket  

# Output should be something like:  
| socket | /tmp/mysql.sock |  

# If different, update your connection string accordingly  

# Use conda environments which handle ARM architecture well  
conda create -n my_env python=3.9  

# For pip packages that don't have ARM wheels:  
arch -arm64 pip install package_name --no-binary :all:  

# Or force x86 emulation if absolutely necessary (not recommended)  
arch -x86_64 /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"  
arch -x86_64 brew install package_name  

FROM --platform=linux/amd64 python:3.9-slim   

RUN apt-get update && apt-get install -y \   
    default-mysql-client \   
    && rm -rf /var/lib/apt/lists/*   

COPY requirements.txt .   
RUN pip install --no-cache-dir -r requirements.txt   

WORKDIR /app   
COPY . .   

CMD ["python", "your_app.py"]   

pip install jupyter ipywidgets   

jupyter notebook --generate-config   

echo "c.NotebookApp.password = ''" >> ~/.jupyter/jupyter_notebook_config.py   
echo "c.NotebookApp.token = ''" >> ~/.jupyter/jupyter_notebook_config.py   

jupyter notebook