擅长:python、mysql、java
<p>以下是查询的多个步骤实现:</p>
<pre><code>import pandas as pd
df = pd.DataFrame(data={'Number': ['ABC', 'BCD', 'CDE', 'DEF', 'FEG'],
'Col1': [True, True, False, False, True],
'Col2': ['SFG', None, 'SFG', None, 'JJI']})
cond1 = df.Col1 & ~df.Col2.isnull()
cond2 = df.Col1 & df.Col2.isnull()
cond3 = ~df.Col1 & ~df.Col2.isnull()
selects = [df[cond1].Number + ',' + df[cond1].Col2,
df[cond2].Number,
df[cond3].Col2]
result = pd.concat(selects).sort_index()
</code></pre>
<p><code>result</code>是(与@MaxU预测相同)</p>
<pre><code>0 ABC,SFG
1 BCD
2 SFG
4 FEG,JJI
dtype: object
</code></pre>