Answers for "dataframe join example"

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')

join pandas dataframe by column

df_outer = pd.merge(df1, df2, on='id', how='outer')
df_inner = pd.merge(df1, df2, on='id', how='inner')

pandas join dataframe

#https://pandas.pydata.org/docs/user_guide/merging.html