我无法从数据帧保存到 postgresql

Question

import pandas as pd
import requests as rq
from sqlalchemy import create_engine

engine = create_engine('postgresql+psycopg2://postgres:3434@127.0.0.1/postgres')

temp = pd.DataFrame()
df = pd.DataFrame()

vehicleList = {"LX59ANR", "SN63NBK", "YY64GRU"}

for ids in vehicleList:
    r = rq.get('https://api.tfl.gov.uk/Vehicle/' + ids + '/Arrivals')
    r = r.text
    temp = pd.read_json(r)

    temp['Type'] = ids

    df = pd.concat([df, temp], sort=False).reset_index(drop=True)
    df.head(0).to_sql('tfl_bus', engine, if_exists='replace', index=False)  # truncates the table

Hello. cannot save data from pandas(dataframe) to postgresql. only column names occurred.

I removed head(0) result like this

Answer 1

df.head(0) needs to be replaced with just df .

The head(0) strips away the actual data leaving the columns...

Answer 2

This work , I added this line : df['timing'] = list(map(lambda x: json.dumps(x), df['timing']))

import sqlalchemy as sa
import psycopg2
import requests as rq
import pandas as pd
import json

r = rq.get('https://api.tfl.gov.uk/Vehicle/SN63NBK/Arrivals')
temp = pd.DataFrame()
df = pd.DataFrame()
r = r.text
temp = pd.read_json(r)
temp['Type'] = '1'
df = pd.concat([df, temp], sort=False).reset_index(drop=True) 
engine=sa.create_engine('postgresql+psycopg2://postgres:3434@127.0.0.1/postgres')
df['timing'] = list(map(lambda x: json.dumps(x), df['timing']))
df.to_sql('tfl_bus2', engine, if_exists='replace', index=False)