擅长:python、mysql、java
<p>如果两个<code>df</code>中的联接只有相同的列,则将<a href="http://pandas.pydata.org/pandas-docs/stable/generated/pandas.merge.html" rel="nofollow noreferrer">^{<cd1>}</a>与{a2}一起使用:</p>
<pre><code>df = pd.merge(df1,df2.drop_duplicates())
print (df)
ID1 ID2 Count Code
0 foo bar 6 Z
1 fizz buzz 5 A
</code></pre>
<p>如果只在<code>ID</code>列中需要检查重复:</p>
^{pr2}$
<p>如果有更多列重叠,请添加参数<code>on</code>:</p>
<pre><code>df = pd.merge(df1, df2.drop_duplicates(), on=['ID1','ID2'])
</code></pre>
<hr/>
<p>如果不删除重复行:</p>
<pre><code>df = pd.merge(df1,df2)
print (df)
ID1 ID2 Count Code
0 foo bar 6 Z
1 foo bar 6 Z
2 fizz buzz 5 A
</code></pre>