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Cross join queries will return only those records that have all the array elements you are trying to find. (Note that it is possible to use multiple cross joins in the FROM stanza - but the results will show only those records that have ALL the array elements specified in the cross joins. If a record is missing even a single specified element, it will drop out.) Because of this, you either need to do separate cross-join queries for each needed element, and left-join them together to a list of all records; or else use this method that employs nested json extrat extract statements. 

The following method captures the array elements by using nested json extract statements in the Select stanza. In this example, we're finding three array elements from the the folio_inventory.instance table (: contributors, languages, and subjects):.

-- Get the json extracts in the first query, then aggregate them in the second query. 

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