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Python:如何在mysql结果头中包含表前缀_Python_Python 3.x_Pandas_Sqlalchemy_Pymysql - Fatal编程技术网

Python:如何在mysql结果头中包含表前缀

Python:如何在mysql结果头中包含表前缀,python,python-3.x,pandas,sqlalchemy,pymysql,Python,Python 3.x,Pandas,Sqlalchemy,Pymysql,我需要在python中执行以下SQL查询 SELECT table_a.company, table_b.company FROM table_a LEFT JOIN table_b ON table_a.id = table_b.id 但问题是,当我运行代码时(尝试使用pymysql(cursor.execute)和pandas(pd.read\u sql)),它们显示 | company | company | -------------------------

我需要在python中执行以下SQL查询

SELECT table_a.company, table_b.company
FROM table_a
LEFT JOIN table_b ON table_a.id = table_b.id
但问题是,当我运行代码时(尝试使用
pymysql
(cursor.execute)和
pandas
(pd.read\u sql)),它们显示

| company        | company        |
-----------------------------------
| <some company> | <some company> |
  • Pymysql

  • 如果有任何帮助,我们将不胜感激。

    如何
    选择表a.company作为“表a.company”…
    ?我避免使用别名,因为我有时需要使用通配符,比如
    表a.*
    我已经更新了问题。感谢回复如何选择表a.company作为“表a.company”…?我避免使用别名,因为我有时需要使用通配符,比如
    表a.*
    我已经更新了问题。谢谢你的回复
    | table_a.company        | table_b.company        |
    ---------------------------------------------------
    | <some company>         | <some company>         |
    
    engine = sqlalchemy.create_engine(connection_string)
    df = pd.read_sql(text(query), engine, chunksize=chunksize):
    print(df)
    
    engine = pymysql.connect(host=host, user=user, password=passw, port=port, db=database)
    cursor = engine.cursor()
    cursor.execute(query)
    result = cursor.fetchmany(chunksize)
    num_fields = len(cursor.description)
    field_names = [i[0] for i in cursor.description]
    df = pd.DataFrame(columns=field_names, data=result)
    print(df)