Example 1: merge two dataframes based on column
df_outer = pd.merge(df1, df2, on='id', how='outer')
df_outer
Example 2: join on column pandas
df1.merge(df2,on='columnName',how='left')
Example 3: pandas left join
df.merge(df2, left_on = "doc_id", right_on = "doc_num", how = "left")
Example 4: combining 2 dataframes pandas
df_3 = pd.concat([df_1, df_2])
Example 5: pandas merge multiple dataframes
import pandas as pd
from functools import reduce
data_frames = [df1, df2, df3]
df_merged = reduce(lambda left,right: pd.merge(left,right,on=['key_col'],
how='outer'), data_frames)
Example 6: pandas merge python
import pandas as pd
df1 = pd.DataFrame({'lkey': ['foo', 'bar', 'baz', 'foo'],
'value': [1, 2, 3, 5]})
df2 = pd.DataFrame({'rkey': ['foo', 'bar', 'baz', 'foo'],
'value': [5, 6, 7, 8]})
df1.merge(df2, left_on='lkey', right_on='rkey')