merge 2 dataframes on 3 columns syntax python 3 code example

Example 1: join on column pandas

# df1 as main df and use the feild from df2 and map it into df1

df1.merge(df2,on='columnName',how='left')

Example 2: merge two columns name in one header pandas

df['A'] = df[a_cols].apply(' '.join, axis=1)