pandas merge df many to many without duplicates

Question

suppose i have two df like below:

import pandas as pd

data_dic = {
    \"a\": [0,0,1,2],
    \"b\": [3,3,4,5],
    \"c\": [6,7,8,9]
}
df1 = pd.DataFrame(dat         


        

Answer 1

You could also drop duplicates after the merge

data_dic = {
    "a": [0,0,1,2],
    "b": [3,3,4,5],
    "c": [6,7,8,9]
}
df1 = pd.DataFrame(data_dic)

data_dic = {
    "a": [0,0,1,2],
    "b": [3,3,4,5],
    "d": [10,10,12,13]
}
df2 = pd.DataFrame(data_dic)


df3 = pd.merge(df1, df2, how='inner', on=['a', 'b']).drop_duplicates()

df3:

   a  b  c   d
0  0  3  6  10
2  0  3  7  10
4  1  4  8  12
5  2  5  9  13