Function backup tabel ke CSV - PostgreSQL

CREATE OR REPLACE FUNCTION "audittable"."backup_logs"()
  RETURNS "pg_catalog"."trigger" AS $BODY$
   
    DECLARE
    filename text :='/home/ukabima/backups/log_backups/loggedtransactions_' || CURRENT_DATE ||'.txt';
   
  BEGIN
     IF ((SELECT count(*) from audittable.tbl_loggedtransactions) >500000) THEN

EXECUTE'COPY audittable.tbl_loggedtransactions TO ''' || filename || '''';

-- COPY audittable.tbl_loggedtransactions TO '/home/ukabima/backups/log_backups/mamanoseng3_loggedtransactions.csv' DELIMITER ',' CSV HEADER ;
       
DELETE FROM audittable.tbl_loggedtransactions;
END IF;
return NULL;
end;
$BODY$
  LANGUAGE plpgsql VOLATILE
  COST 100