pd merge on multiple columns

1new_df = pd.merge(A_df, B_df,  how='left', left_on=['A_c1','c2'], right_on = ['B_c1','c2'])

1#suppose you have two dataframes df1 and df2, and 
2#you need to merge them along the column id
3df_merge_col = pd.merge(df1, df2, on='id')

1# Joins with another DataFrame
2
3df.join(df2, df.name == df2.name, 'outer').select(
4  df.name, df2.height).collect()
5# [Row(name=None, height=80), Row(name=u'Bob', height=85), Row(
6#   name=u'Alice', height=None)]
7
8df.join(df2, 'name', 'outer').select('name', 'height').collect()
9# [Row(name=u'Tom', height=80), Row(name=u'Bob', height=85), Row(
10#   name=u'Alice', height=None)]
11
12cond = [df.name == df3.name, df.age == df3.age]
13df.join(df3, cond, 'outer').select(df.name, df3.age).collect()
14# [Row(name=u'Alice', age=2), Row(name=u'Bob', age=5)]
15
16df.join(df2, 'name').select(df.name, df2.height).collect()
17# Row(name=u'Bob', height=85)]
18
19df.join(df4, ['name', 'age']).select(df.name, df.age).collect()
20# [Row(name=u'Bob', age=5)]

1m = {'left_only': 'df1', 'right_only': 'df2', 'both': 'df1, df2'}
2
3result = df1.merge(df2, on=['A'], how='outer', indicator='B')
4result['B'] = result['B'].map(m)
5
6result