AI engineering glossary · NumPy pandas visualization
What is pandas merge?
pandas merge (also called merge, pd.merge): A pandas function that combines two DataFrames by matching values in key columns, like a database join. The how option chooses inner, left, right or outer behaviour, and mismatched or repeated keys can change the number of rows, so row counts should be checked afterwards.
pandas merge: an example
orders.merge(customers, on='customer_id', how='left') adds customer details to each order, keeping orders with no match.