Phase 0: Working with Data in Python · ~25 minutes · Python · pandas

JSON and Nested Data

Rows and columns assume the data is already flat. Nothing about a real API response guarantees that, and json_normalize only flattens as deep as you tell it to.

Hiring signal: Checks a flattened DataFrame's actual columns before trusting them, rather than assuming a nested field automatically became usable

What you will learn

Explain why nested JSON doesn't fit directly into a DataFrame's rows and columns
Use pd.json_normalize to flatten a real nested API response
Diagnose what happens to a nested field when flattening depth isn't specified deep enough
Predict the column names json_normalize produces from a given nested structure

Introduction

Type: Learn Languages: Python, pandas Prerequisites: Lesson 04 (Reading Real, Ugly Files) Time: ~25 minutes

Objective

Learning objectives

Explain why nested JSON doesn't fit directly into a DataFrame's rows and columns
Use pd.json_normalize to flatten a real nested API response
Diagnose what happens to a nested field when flattening depth isn't specified deep enough
Predict the column names json_normalize produces from a given nested structure

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