Pay attention to cardinality & grain when UNNESTING in BigQuery!
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Senior Data Engineer • Contractor / Freelancer • GCP & AWS Certified
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BigQuery Arrays & Structs
Part 14 of 19
Everything you need to work effectively with nested and repeated data in BigQuery — ARRAY, STRUCT, UNNEST, ARRAY_AGG, and related functions.
The relationship between ARRAY_AGG and UNNEST
title: "The relationship between ARRAY_AGG and UNNEST" seoTitle: "BigQuery ARRAY_AGG vs UNNEST: Opposite Operations Explained" seoDescription: "ARRAY_AGG packs rows into an ARRAY and UNNEST unpacks an ARRAY back into rows — they are inverse operation...
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