如何调试cursor.execute（psycopg2）为NoneType

Question

我尝试对我的postgres数据库运行SQL，

我通过的连接对象

import psycopg2
conn_string = "host='localhost' port='5432' dbname='postgres' user='postgres' password='mysecretpassword'"
conn = psycopg2.connect(conn_string)

似乎还可以

result = cursor.execute(
"""
select 
* 
from 
planet_osm_point limit 10
""")

结果是Nonetype，所以一定有问题吗？

我做错了什么？ 我该如何调试呢？

Answer 1

cursor.execute()仅执行查询，不获取任何数据。 为了接收数据，您将需要调用cursor.fetchall()或cursor.fetchone() 。

import psycopg2
conn_string = "host = 'localhost' port = '5432' dbname = 'postgres' user = 'postgres' password = 'mysecretpassword'"
conn = psycopg2.connect(conn_string)
cursor.execute(
""" 
select 
* 
from 
planet_osm_point limit 10
""")

result = cursor.fetchall()