Unnest JSON Array into Rows (pseudo-json_each)SQL

Editor's note: as APIs and applications increasingly represent tabular data in JSON format, we sometimes want the comfort of seeing it as rows, queryable in SQL. DuckDB has a great extension for parsing JSON, including the ability to convert into a DuckDB list which can then be unnested into rows.

Execute this SQL

select 
    -- Split DuckDB list into multiple rows
    unnest(
        -- Convert JSON array into DuckDB list of JSON elements
        from_json(
            json('[{"col1":1, "col2":2}, {"col1":10, "col2":20}]'),
            '["JSON"]'
        )
    );
/* 
Returns:
{"col1":1,"col2":2}
{"col1":10,"col2":20}
*/
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Alex Monahan

Edited 02/23/24