How to resolve error when running dynamic PostreSQL function - postgresql

Question

I have a function that takes 3 parameters: huc, id_list, and email.
CREATE OR REPLACE FUNCTION my_app.job_batch(
huc text,
input_list text[],
email text
) RETURNS VOID AS
$$
DECLARE
id text;
BEGIN
FOREACH id IN ARRAY input_list LOOP
EXECUTE 'SELECT * FROM my_app.my_funct(
' || huc || '::text,
' || id || '::text,
' || email || '::text)';
END LOOP;
END;
$$
LANGUAGE plpgsql;
When I try to run the function however, it throws an error: ERROR: column "myhu4" does not exist
SELECT * FROM spg_app.append_spg_job_batch('MYHUC4', array['1021', '1025','1026','1027','0701','0702','0703','0708','0709'], 'myemail#gmail.com');
Why is it referring to myhuc4 as a column and why is displaying it in lower case. Is my syntax below to run the function with those 3 parameters incorrect? Note: If I run the below hardcoded version, it runs fine:
DO $$
DECLARE
id_list text[] := array['1021', '1025','1026','1027','0701','0702','0703','0708','0709'];
id text;
BEGIN
FOREACH id in ARRAY id_list LOOP
EXECUTE 'SELECT * FROM my_app.my_funct(
''MYHU4''::text,
' || id || '::text,
''myemail#gmail.com''::text)'
END LOOP;
END;
$$
LANGUAGE plpgsql;

Answer 1

I suggest to use parameters instead of bad practice of stitching strings, as follows:
CREATE OR REPLACE FUNCTION my_app.job_batch(
huc text,
input_list text[],
email text
) RETURNS VOID AS
$$
DECLARE
id text;
BEGIN
FOREACH id IN ARRAY input_list LOOP
execute format ('SELECT * FROM my_app.my_funct($1, $2, $3)')
using huc, id, email;
END LOOP;
END;
$$
LANGUAGE plpgsql;
as shown in official docs https://www.postgresql.org/docs/current/plpgsql-statements.html#PLPGSQL-STATEMENTS-EXECUTING-DYN