AI Python+SQL数据分析与应用

engine = create_engine(connection_string)

connection_string = f"mysql+pymysql://{safe_user}:{safe_password}@{DB_HOST}:{DB_PORT}/{target_db}?charset=utf8mb4"

tables = ['dim_channels', 'dim_customers', 'dim_date', 'dim_products', 'fact_orders']    print(f"=== 数据库 {target_db} 各表数据概览 ===\n")    for table in tables:        # 查询各表总行数        count_query = f"SELECT COUNT(*) as total_rows FROM {table};"        total_rows = pd.read_sql(count_query, con=engine).iloc[0]['total_rows']        # 查询前 3 行进行预览        preview_query = f"SELECT * FROM {table} LIMIT 3;"        df_preview = pd.read_sql(preview_query, con=engine)        print(f"📌 数据表: {table} (总计 {total_rows} 行)")        display(df_preview)        print("-" * 60 + "\n")