The following query passes SQL and compilation:

CREATE TABLE map_of_int_tbl(
id INT,
c1 MAP<INT, INT> NOT NULL,
c2 MAP<INT, INT>);


CREATE MATERIALIZED VIEW v AS SELECT *
FROM map_of_int_tbl;

But the following ad-hoc query that listens to the output of view v:
SELECT * FROM v;

Produces the following error:
Arrow error: Json error: Only UTF8 keys supported by JSON MapArray Writer: got Int32'