python - pandasql 中的查询错误

Question

我对 PandaSQL 很陌生，以前从未使用过它。到目前为止，这是我的代码：

import pandas as pd
from pandasql import sqldf
import numpy as np

tasks = pd.read_csv("C:/Users/RMahesh/Documents/TASKS_Final_2.csv", encoding='cp1252')
query = """SELECT Work Item Id, Parent Work Item Id, MAX(Remaining Work) 
FROM TASKS 
GROUP BY Work Item Id, Parent Work Item Id;"""

df = sqldf(query, locals()))
print(df.head(5))

我收到此错误：

'pandasql.sqldf.PandaSQLException: (sqlite3.OperationalError) near "Id": syntax error [SQL: 'SELECT Work Item Id, Parent Work Item Id, MAX(Remaining Work) \n'

任何帮助都会很棒！

编辑：在执行以下其他用户的一些建议后，这是我的工作代码：

import pandas as pd
from pandasql import sqldf
import numpy as np
tasks = pd.read_csv("C:/Users/RMahesh/Documents/TASKS_Final_2.csv", encoding='cp1252',  low_memory=False)

query = """SELECT [Work Item Id], [Parent Work Item Id], MAX([Remaining Work]) 
FROM tasks 
GROUP BY [Work Item Id], [Parent Work Item Id];"""

print(sqldf(query, locals()))

标签： pythonpython-3.xpandaspandasql

Answer 1

如果您的列名包含空格，则必须引用它们以使 SQL 有效：

query = """SELECT `Work Item Id`, `Parent Work Item Id`, MAX(`Remaining Work`) 
FROM TASKS 
GROUP BY `Work Item Id`, `Parent Work Item Id`;"""

或者

query = """SELECT [Work Item Id], [Parent Work Item Id], MAX([Remaining Work]) 
FROM TASKS 
GROUP BY [Work Item Id], [Parent Work Item Id];"""

取决于 PandaSQL 期望的风格。