join two pandas dataframe using a specific column

Question

I am new with pandas and I am trying to join two dataframes based on the equality of one specific column. For example suppose that I have the followings:

df1
A    B    C
1    2    3
2    2    2

df2
A    B    C
5    6    7
2    8    9

Both dataframes have the same columns and the value of only one column (say A) might be equal. What I want as output is this:

df3
A    B    C   B    C
2    8    9   2    2

The values for column 'A' are unique in both dataframes.

Thanks

Solution 1

pd.concat([df1.set_index('A'),df2.set_index('A')], axis=1, join='inner')

If you wish to maintain column A as a non-index, then:

pd.concat([df1.set_index('A'),df2.set_index('A')], axis=1, join='inner').reset_index()

Solution 2

Alternatively, you could just do:

df3 = df1.merge(df2, on='A', how='inner', suffixes=('_1', '_2'))

And then you can keep track of each value's origin