如何在 Pandas 数据框中编写 sql 查询

Question

如何在熊猫数据框中编写以下查询

SELECT * FROM Table
WHERE a = "S"
AND b IS NOT NULL
AND c IS NOT NULL;

Answer 1

如果你正在寻找一个等效的命令来在熊猫数据框中获得相同的结果，你可以试试这个

df = pd.DataFrame({'a':['S','T','S'],'b':[None, 1, 2],'c':[1,2,3]})
df = df.dropna(subset=['b','c'])
df.loc[df.dropna(subset=['b','c'])['a'] == 'S']

原始数据框

   a    b  c
0  S  NaN  1
1  T  1.0  2
2  S  2.0  3

输出

    a   b   c
2   S   2.0 3