Check if property exists in an object inside array in JSONB field in Postgres
Use an EXISTS in which you use jsonb_array_elements() to get the arrays' elements and check -&gt;'d'-&gt;'f' for NULL.

SELECT * 
       FROM jsonData
       WHERE EXISTS (SELECT *
                            FROM jsonb_array_elements(data-&gt;'c')
                            WHERE value-&gt;'d'-&gt;'f' IS NOT NULL);


SQL Fiddle