Merging Two Dataframes In Python Pandas

I have a dataframe A: a 1 a 2 b 1 b 2 Another dataframe B: a 3 a 4 b 3 I want my result dataframe to be like a 1 3 a 1 4 a 2 3 a 2 4 b 1 3 b 2 3 I wondering how I can get

Solution 1:

A simple merge using df.merge does this:

df1.merge(df2, on=['A'])

   A  B_x  B_y
0  a    1    3
1  a    1    4
2  a    2    3
3  a    2    4
4  b    1    3
5  b    2    3