Python:无法连接到 Postgresql 数据库

Question

我一直在使用以下代码行最长时间，没有任何障碍，但今天它似乎产生了以下错误，我无法弄清楚原因。奇怪的是，我还有其他使用相同代码的脚本，它们似乎都可以工作......

import pandas as pd
import psycopg2
link_conn_string = "host='<host>'  dbname='<db>'  user='<user>'  password='<pass>'"
conn = psycopg2.connect(link_conn_string)
df = pd.read_sql("SELECT * FROM link._link_bank_report_lms_loan_application", link_conn_string)

错误信息:

    "Could not parse rfc1738 URL from string '%s'" % name)
sqlalchemy.exc.ArgumentError: Could not parse rfc1738 URL from string 'host='<host>'  dbname='<db>'  user='<user>'  password='<pass>''

Answer 1

改 link_conn_string就像here :

postgresql://[user[:password]@][netloc][:port][/dbname][?param1=value1&...]

例如:

>>> import psycopg2
>>> cs = 'postgresql://vao@localhost:5432/t'
>>> c = psycopg2.connect(cs)
>>> import pandas as pd
>>> df = pd.read_sql("SELECT now()",c)
>>> print df;
                               now
0 2017-02-27 21:58:27.520372+00:00