How do I join two DataFrames in Pandas using Jupyter Notebooks?

How do I join two DataFrames in Pandas using Jupyter Notebooks?

You can use the merge() function in Pandas to join two DataFrames. What type of join do you need: inner, outer, left, or right?

I need to perform a left join.

You can do that by using pd.merge(df1, df2, how='left', on='key_column'). Replace df1 and df2 with your DataFrames and key_column with the column you want to join on.

What if the key columns have different names in each DataFrame?

In that case, you can specify the left and right key columns using left_on and right_on parameters: pd.merge(df1, df2, how='left', left_on='key1', right_on='key2').

Can you show me an example with sample DataFrames?

Sure! Here's a quick example:

import pandas as pd

df1 = pd.DataFrame({'key1': ['A', 'B', 'C'], 'value1': [1, 2, 3]})
df2 = pd.DataFrame({'key2': ['A', 'B'], 'value2': [4, 5]})

result = pd.merge(df1, df2, how='left', left_on='key1', right_on='key2')
print(result)