Psycopg3 无法异步连接

Question

无法使用异步 psycopg3 连接 postgres 数据库:

import asyncio
import psycopg

async def main():
    async with await psycopg.AsyncConnection.connect('postgresql://xxxxxxxxxxx') as con:
        async with con.cursor() as cur:
            print(await cur.execute('select 1 a').fetchall())

if __name__ == '__main__':
    asyncio.run(main())

我收到错误：

psycopg.InterfaceError: Psycopg cannot use the 'ProactorEventLoop' to run in async mode. Please use a compatible event loop, for instance by setting 'asyncio.set_event_loop_policy(WindowsSelectorEventLoopPolicy())'

在 Windows 10、Python 3.9、Psycopg 3.0.8 上

Answer 1

这是工作解决方案

import asyncio
import sys

import psycopg


async def main():

    async with await psycopg.AsyncConnection.connect('postgresql://xxxxxxxxxxx') as con:
        async with con.cursor() as cur:
            print(await (await cur.execute('select 1 a')).fetchall())

if __name__ == '__main__':

    if sys.platform == "win32":
        asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy())

    asyncio.run(main())