通过pd.to_sql()将DataFrame写入Mysql
循环创建表,并且创建主键、外键
import pandas as pd from sqlalchemy import create_engine from sqlalchemy.types import NVARCHAR, Float, Integer def pd2sql(): """ to_sql目前只支持两类mysql引擎一个是sqlalchemy和sqlliet3 :return: """ # 初始化数据库连接,使用pymysql模块 # MySQL的用户:root, 密码:147369, 端口:3306,数据库:mydb # ?charset=utf8 指定数据库编码 engine = create_engine('mysql+pymysql://root:@localhost:3306/pandas2mysql?charset=utf8') conn = engine.connect() for i in range(1, 10): # 指定字段的数据类型 dtypedict = { 'index_code': NVARCHAR(length=255), 'date': NVARCHAR(length=255), 'open': NVARCHAR(length=255), 'close': NVARCHAR(length=255), 'low': NVARCHAR(length=255), 'high': NVARCHAR(length=255), 'volume': NVARCHAR(length=255), 'money': NVARCHAR(length=255), 'change': NVARCHAR(length=255) } csv_path = r'E:\data\yucezhe\trading-data-push.20190201\2019-02-01 index data.csv' # 读取本地CSV文件 df = pd.read_csv(csv_path).head() # 将DataFrame储存为MySQL中的数据表,不储存index列 df.to_sql(f'csv_table{i}', engine, if_exists='replace', index=False, dtype=dtypedict) # 执行原生sql语句 # 设置主键 conn.execute(f"alter table csv_table{i} add constraint p_key primary key (index_code)") # 从表设置外键 if i%2 == 0: conn.execute( f"alter table csv_table{i-1} add foreign key (index_code) references csv_table{i}(index_code)") print(f"Write to MySQL successfully! ---- csv_table{i}") engine.dispose() pd2sql() # 对已存在的表做主键:alter table csv_short1 add constraint p_key primary key (index_code); # 对已存在的表做外键:alter table csv_short1 add foreign key (index_code) references csv_short2(index_code); # 内连接查询:select * from a,b where a.x = b.x