python - Pandas 连接 2 个数据框

Question

我有 2 个数据框:

>>> result
         id   order_nr
0   3131334  334756912
0   3131312  386517432
0   3131309  356299432
0   3131205  397514312
          ...

>>> OMSdf
     order_nr            status  refund_amount
0   377766482  already_canceled              0
1   348722582  already_canceled              0
2   395287472           on_hold              0
3   345883652  already_canceled              0
          ...

这 2 个数据帧在“order_nr”字段中有一些共同的值:

>>> result[result['order_nr'] == '377766482']
        id   order_nr
0  3129153  377766482

>>> OMSdf[OMSdf['order_nr'] == '377766482']
    order_nr            status  refund_amount
0  377766482  already_canceled              0

但我尝试将它们结合在一起:

resultfinal = result.join(OMSdf, on='order_nr', how='inner', lsuffix='', rsuffix='_oms', sort=False)

结果为空:

>>> resultfinal
Empty DataFrame
Columns: [id, order_nr, order_nr_oms, status, refund_amount]
Index: []

Answer 1

使用下面的代码

df_merged = pd.merge(result, OMSdf, how='inner')

就您而言，您可以在加入之前将 order_nr 作为两个数据帧的索引，如下所示

result.index = result['order_nr']
OMSdf.index = OMSdf['order_nr']