取得 SQL 資料時出錯

Question

所以我只是從資料庫中提取數據，遇到以下錯誤。 代碼如下：

import pandas as pd
import sqlalchemy

engine = sqlalchemy.create_engine("mysql pymysql://root:@localhost:3306/haider")
df = pd.read_sql_table("ahmed", engine)

執行此程式碼時出現以下錯誤：

--------------------------------- ------------------------------------------
AttributeError Traceback (most recent call last)
Cell In [46], line 1
----> 1 df = pd.read_sql_table("ahmed", engine)

File E:\python\lib\site-packages\pandas\io\sql.py:286, in read_sql_table(table_name, con, schema, index_col, coerce_float, parse_dates, columns, chunksize)
    282 raise ValueError(f"Table {table_name} not found")
    284 # error: Item "SQLiteDatabase" of "Union[SQLDatabase, SQLiteDatabase]"
    285 # 有 no attribute "read_table"
--> 286 table = pandas_sql.read_table( # type: ignore[union-attr]
    287 table_name,
    288 index_col=index_col,
    289 coerce_float=coerce_float,
    290 parse_dates=parse_dates,
    291 columns=columns,
    292 chunksize=chunksize,
    293 )
    295 if table is not None:
    296 return table

File E:\python\lib\site-packages\pandas\io\sql.py:1460, in SQLDatabase.read_table(self, table_name, index_col, coerce_float, parse_dates, columns, schema, chunksize)
   1417 """
   1418 Read SQL database table into a DataFrame.
   1419
   (...)
   1457
   1458 """
   1459 table = SQLTable(table_name, self, index=index_col, schema=schema)
-> 1460 return table.read(
   1461 coerce_float=coerce_float,
   1462 parse_dates=parse_dates,
   1463 columns=columns,
   1464 chunksize=chunksize,
   1465 )

File E:\python\lib\site-packages\pandas\io\sql.py:1003, in SQLTable.read(self, coerce_float, parse_dates, columns, chunksize)
   1001 else:
   1002 sql_select = select(self.table)
-> 1003 result = self.pd_sql.execute(sql_select)
   1004 column_names = result.keys()
   1006 if chunksize is not None:

File E:\python\lib\site-packages\pandas\io\sql.py:1405, in SQLDatabase.execute(self, *args, **kwargs)
   1403 def execute(self, *args, **kwargs):
   1404 """Simple passthrough to SQLAlchemy connectable"""
-> 1405 return self.connectable.execution_options().execute(*args, **kwargs)

AttributeError: 'OptionEngine' object has no attribute 'execute'

注意：我的資料庫沒有任何密碼，其次我也已經安裝了 PyMySQL。

我試圖解釋使用 python 獲取 sql 資料時遇到的錯誤，我希望得到該問題的解決方案。

Answer 1

我強烈建議您嘗試以下操作

engine = sqlalchemy.create_engine("mysql+pymysql://root:@localhost:3306/haider").connect()

我認為您可能缺少最後的 connect() 部分。