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This page describes how to parse JSONs in Wrangler. If the JSON has arrays, this will be a short tutorial to explain how the arrays can be exploded/flattened into columns for further processing and cleanup.
Parsing JSON
Steps to follow:
Go to CDF instance.
Navigate to Wrangler from the sidebar (appears by clicking the hamburger icon in the navbar).
From the a Wrangler source (GCS or BigQuery), read a JSON file to Wrangle.
Once navigated to Wrangler tab, open the dropdown on the column and choose Parse → JSON.
After Step 4, the fields in the JSON will form the column. Identify the column that has rows.
Open the drop-down from that specific column and select Explode → Array (by flattening).
This will explode the elements in the JSON array as individual data in the same column in Wrangler.
After step 7 further directives can be applied based on cleanup needed.