My "variable number of bind variables for dynamic SQL" solution. Comments?

I'm a postgres noob, so I am looking for advice/ comments.
My example code here demonstrates the solution to a real world situation
where I am converting a PL/SQL Package (Oracle) to a pgPL/SQL function. The
original package constructs an elaborate SELECT statement which can look
extremely different depending on the the values of various parameters and
the results of table lookups. The only thing that does not vary are the
columns of the constructed SELECT statement.

fbind will be called by the function shown immediately after this

> CREATE OR REPLACE FUNCTION fbind(
>
> IN p_psudo_datatype_i character varying,
>
> IN p_parameter_position_i int)
>
> RETURNS text AS
>
> $BODY$
>
> BEGIN
>
>
>> CASE p_psudo_datatype_i
>
> WHEN 'cvs num' THEN
>
> return '= ANY
>> ((''{''||$'||p_parameter_position_i::text||'||''}'')::bigint[] ) '::text;
>
> WHEN 'bigint' THEN
>
> return '=
>> TO_NUMBER($'||p_parameter_position_i::text||',''99999999999999999999'')
>> '::text;
>
> ELSE
>
> return 'datatype not implemented'::text;
>
> END CASE;
>
>
>> END;$BODY$
>
> LANGUAGE plpgsql VOLATILE
>
> COST 100;
>
>
test driver procedure

DO $$
>
> DECLARE
>
> sql text := 'select vendor_name from tx_vendor WHERE active_flag = ''Y'' ';
>
> v_bind_values text[];
>
> v_vendor_key bigint := 1017;
>
> v_cvs_code2tcode character varying (30) := '2222,5235,7979';
>
> v_vendor_name text;
>
> BEGIN
>
> v_bind_values := array_append(v_bind_values, v_vendor_key::text);
>
> sql := sql || '
>
> and vendor_key'||fbind('bigint'::text,array_length(v_bind_values,1));
>
>
>> -- in a real use situation, the following 2 lines of code may or may not
>> be
>
> -- executed, meaning, we will not know how many bind variables
>
> v_bind_values := array_append(v_bind_values,v_cvs_code2tcode::text);
>
> sql := sql || '
>
> and code2tcode'||fbind('cvs num'::text,array_length(v_bind_values,1));
>
>
>> case array_length(v_bind_values,1)
>
> when 1 then
>
> execute sql into strict v_vendor_name using v_bind_values[1];
>
> when 2 then
>
> execute sql into strict v_vendor_name using v_bind_values[1],
>> v_bind_values[2];
>
> else
>
> raise exception 'undefined number of bind variables' ;
>
> end case;
>
>
>> raise notice '
>
> sql:%', sql ;
>
> raise notice '
>
> v_vendor_name:%',v_vendor_name;
>
>
>> END$$;
>
>
RUN results ... shows the SQL statement that was constructed

> NOTICE:
>
> sql:select vendor_name from tx_vendor WHERE active_flag = 'Y'
>
> and vendor_key= TO_NUMBER($1,'99999999999999999999')
>
> and code2tcode= ANY (('{'||$2||'}')::bigint[] )
>
> NOTICE:
>
> v_vendor_name:Irwin Union Bank
>
>
>> Query returned successfully with no result in 15 msec.
>
>
All comments or suggestions for improvement are welcome.
Regards,
Mike