pandas merge code example

Example 1: merge on index pandas

pd.merge(df1, df2, left_index=True, right_index=True)

Example 2: pd merge on multiple columns

new_df = pd.merge(A_df, B_df,  how='left', left_on=['A_c1','c2'], right_on = ['B_c1','c2'])

Example 3: 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 4: pandas left join

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

Example 5: combining 2 dataframes pandas

df_3 = pd.concat([df_1, df_2])

Example 6: joins in pandas

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