您可以使用pandas.merge（https://pandas.pydata.org/docs/reference/api/pandas.DataFrame.merge.html）执行此操作，如下所示：

import numpy as np
import pandas as pd

df1 = pd.DataFrame({
    'A': ['foo', 'bar', 'foo', 'bar', 'foo', 'bar', 'fo', 'fool'],
    'C': [10, 10, 10, 30, 50, 60, 50, 8],
    'D': [9, 8, 7, 6, 5, 4, 3, 2],
    'id': [1, 2, 3, 4, 5, 6, 7, 8],
})
print(df1)
"""
      A   C  D  id
0   foo  10  9   1
1   bar  10  8   2
2   foo  10  7   3
3   bar  30  6   4
4   foo  50  5   5
5   bar  60  4   6
6    fo  50  3   7
7  fool   8  2   8
"""
df2 = pd.DataFrame({
    'id': [1, 6, 7, 8],
    'A': [np.NAN, np.NAN, np.NAN, np.NAN],
    'C': [np.NAN, np.NAN, np.NAN, np.NAN]
})
print(df2)
"""
   id   A   C
0   1 NaN NaN
1   6 NaN NaN
2   7 NaN NaN
3   8 NaN NaN
"""
df3 = pd.merge(df1[['id', 'A', 'C']], df2['id'], how='inner', on='id')
print(df3)
"""
   id     A   C
0   1   foo  10
1   6   bar  60
2   7    fo  50
3   8  fool   8
"""