擅长:python、mysql、java
<p>使用地图:</p>
<pre><code>lookup = df1.groupby(['transaction_id'])['amount'].sum()
df2['revenue'] = df2.transaction_id.map(lookup)
print(df2)
Output
transaction_id location_id customer_id revenue
0 AJGDO-12304 2131234 1234 140
1 ODSKF-99130 213124 1345 200
</code></pre>