Pandas Joins for Spreadsheet Users
John Miller
Principal Data Scientist
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Common situations
Concatenate data by row or column
pd.concat([df1, df2], axis=0)
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One-to-one, VLOOKUP-style joins
pd.merge(left_df, right_df,
how='inner',
on='key_column')
$$ Joins (merges) on key column
df1.merge(df2, how='inner',
on='key_column')
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Joins on unique index
df1.join(df2, how='left')
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Advanced parameters
pd.merge_ordered(left_df, right_df, how='outer')
pd.merge_asof(left_df, right_df, direction='backward')
Pandas Joins for Spreadsheet Users