Routine for reading data uses another routine to read some data

Copy SQL

WITH select_routines AS (SELECT 
  pg_namespace.nspname AS specific_schema, 
  pg_proc.proname AS routine_name, 
  pg_proc.proname || '_' || pg_proc.oid AS specific_name,
  pg_get_function_identity_arguments(pg_proc.oid) AS parameters,
  CASE WHEN pg_proc.prokind='f' THEN 'FUNCTION'
  WHEN pg_proc.prokind='p' THEN 'PROCEDURE'
  WHEN pg_proc.prokind='w' THEN 'WINDOW FUNCTION' END AS routine_type,
 regexp_replace(pg_get_functiondef(pg_proc.oid),'[\r\n]','<br>','g')  AS routine_src,
  pg_language.lanname AS routine_language
FROM 
  pg_catalog.pg_proc, 
  pg_catalog.pg_namespace,
  pg_catalog.pg_language
WHERE 
  pg_proc.pronamespace = pg_namespace.oid 
  AND pg_proc.prolang = pg_language.oid  
  AND pg_proc.prokind<>'a'  
  AND pg_get_functiondef(pg_proc.oid)~*'([[:space:]]*SELECT[[:space:]]|[[:space:]]*PERFORM[[:space:]]).+[[:space:]]FROM[[:space:]]'
  AND pg_get_functiondef(pg_proc.oid)!~*'(insert|update[^;]+set[[:space:]]|delete)'
  AND pg_namespace.nspname NOT IN (SELECT schema_name
FROM INFORMATION_SCHEMA.schemata
WHERE schema_name<>'public' AND
schema_owner='postgres' AND schema_name IS NOT NULL))

SELECT r.specific_schema AS user_schema, r.routine_name AS user_name, r.parameters AS user_parametes, r.routine_type AS user_type, r.routine_src AS user_src,
r2.specific_schema AS used_schema, r2.routine_name AS used_name, r2.parameters AS used_parametes, r2.routine_type AS used_type, r2.routine_src AS used_src
FROM select_routines AS r INNER JOIN INFORMATION_SCHEMA.routine_routine_usage AS rru USING (specific_schema, specific_name)
INNER JOIN select_routines AS r2 ON rru.routine_schema=r2.specific_schema AND rru.routine_name=r2.specific_name
ORDER BY r.specific_schema, r.routine_name, r.parameters;