Answers for "left join in pandas"

pandas left join

df.merge(df2, left_on = "doc_id", right_on = "doc_num", how = "left")

joins in pandas

pd.merge(product,customer,left_on='Product_name',right_on='Purchased_Product')

joins in pandas

pd.merge(product,customer,on='Product_ID')

python dataframe left join

>>> left.merge(right, on='user_id', how='left')