To change the names of the keys in the Avro records, use the SCHEMA custom clause.
SELECT data.toJSON() FROM CSV_TO_AVRO
(
ON (SELECT csvFile FROM myCSVTable09 WHERE id=2)
USING SCHEMA('{"record_delimiter":"#", "field_names": ["a1","a2","a3","a4","a5","a6","a7"]}')
) AS csvAvro ORDER BY data."a1";
Result:
> {"a1":"105","a2":"soap","a3":null,"a4":null,"a5":"1","a6":"0.99","a7":"0.99"}
> {"a1":"55","a2":"bicycle","a3":"red","a4":"boys","a5":"1","a6":"100.00","a7":"100.00"}
> {"a1":"88","a2":"toy boat","a3":"pink","a4":null,"a5":"1","a6":"15.10","a7":"15.10"}
> {"a1":"Item_ID","a2":"Item_Name","a3":"Item_Color","a4":"Item_Style","a5":"Quantity_Purchased","a6":"Item_Price","a7":"Total_Price"}