如何在SQL Server查询中读取为dask DataFrame（attributeError：module＆＃x27; dask.dataframe＆＃x27;没有属性＆＃x27; read_sql_query＆＃x27;）

Question

我目前使用pyodbc读取为pandas dataframe，然后将其转换为dask数据框架。无论如何是否可以直接阅读为Dask DataFrame？

这是我当前正在使用的代码：

import pandas as pd
import numpy as np
from dask.dataframe import from_pandas

def conn_sql_server(file_path):
    
    #Connect to SQL Server
    conn = pyodbc.connect('Driver= {SQL Server Native Client 11.0};'
                          'Server= Server1;'
                          'Database = Database1;'
                          'Trusted_Connection=yes;')
    
    #run query and ouput the result to df
    query = open(file_path, 'r') 
    df = pd.read_sql_query(query.read(), conn, chunksize=10**4)
    
    chunks =[]
    for chunk in df: 
        chunks.append(chunk)
    
    df_comb = pd.concat(chunks)
    
    query.close() 
    
    return df_comb 

#load in as pandas dataframe
data = conn_sql_server('.\input\data pull.sql')

#Convert to dask dataframe
dd = from_pandas(data, npartitions=3)

我尝试使用dd.read_sql_query与PYODBC软件包或sqlalchemy软件包。两者都返回了一个属性：模块'dask.dataframe'没有属性'read_sql_query'

（1）pyodbc：

import dask.dataframe as dd   

def conn_sql_server(file_path):
    
    #Connect to SQL Server
    conn = pyodbc.connect('Driver= {SQL Server Native Client 11.0};'
                          'Server= Server1;'
                          'Database = Database1;'
                          'Trusted_Connection=yes;')
    
    #run query and ouput the result to df
    query = open(file_path, 'r') 
    df = dd.read_sql_query(query.read(), conn)
    
    query.close() 
    
    return df 

data = conn_sql_server('.\input\data pull.sql')

attributeError：模块'dask.dataframe'没有属性'read_sql_query'

（2）sqlalchemy：

from sqlalchemy import create_engine

Server= 'Server1'
Database = 'Database1'
Driver= 'SQL Server Native Client 11.0'
uri = f'mssql://{Server}/{Database}?driver={Driver}'

query = open('.\input\data pull.sql', 'r')
dd.read_sql_query((query.read(), uri))

正如尼克所建议的，我使用Python -M PIP安装DASK分布式-Upgrade 。我还使用以下脚本检查了dask.dataframe模块中列出的所有功能。发现只有read_sql_table，没有read_sql_query

from inspect import getmembers, isfunction
import dask.dataframe as dd
getmembers(dd, isfunction)