What is the difference between join and merge in Pandas?

后端 未结 7 2308
没有蜡笔的小新
没有蜡笔的小新 2020-11-27 09:20

Suppose I have two DataFrames like so:

left = pd.DataFrame({\'key1\': [\'foo\', \'bar\'], \'lval\': [1, 2]})

right = pd.DataFrame({\'key2\': [\'foo\', \'bar         


        
7条回答
  •  -上瘾入骨i
    2020-11-27 09:53

    • Join: Default Index (If any same column name then it will throw an error in default mode because u have not defined lsuffix or rsuffix))
    df_1.join(df_2)
    
    • Merge: Default Same Column Names (If no same column name it will throw an error in default mode)
    df_1.merge(df_2)
    
    • on parameter has different meaning in both cases
    df_1.merge(df_2, on='column_1')
    
    df_1.join(df_2, on='column_1') // It will throw error
    df_1.join(df_2.set_index('column_1'), on='column_1')
    

提交回复
热议问题