Guided Notes
Nested & Repeated Data (JSON)
Querying nested records and arrays — BigQuery STRUCT/ARRAY and JSON in SQL.
Flat vs. nested data
Slide 1 / 5So far every column held one simple value. Nested data packs several related values into one column — a pet's owner column holding the owner's name and age together:
owner = {"name": "Magnus", "age": 9}
The alternative is a separate owners table joined by an ID. Nesting keeps related values together and saves a join; flat tables are simpler to query and update.