CREATE OR REPLACE FUNCTION "public"."check_and_delete_bank" (integer) RETURNS varchar AS'
DECLARE
    Name_Firm Varchar;
    Kod_Banka Integer;
begin
     kod_banka:=$1;
     SELECT Name_kratko INTO Name_firm FROM Firms WHERE id_schet=(SELECT id_schet FROM schet_firms WHERE id_banka=kod_banka);
     if FOUND then
          return Name_Firm;
     else
          SELECT Name_kratko INTO Name_firm FROM Klient WHERE id_scheta=(SELECT id_scheta FROM scheta_klienta WHERE id_banka=kod_banka);
          if FOUND then
               return Name_Firm;
          else
               SELECT Bank_Name INTO Name_Firm FROM bank WHERE id_banka=kod_banka FOR UPDATE;
               if NOT FOUND then
                  Return ''Не могу заблокировать данные'';
               else
                  DELETE FROM bank WHERE id_banka=kod_banka;
                  return ''Удалил!'';
               end if;
          end if;
     end if;
end;

'LANGUAGE 'plpgsql' VOLATILE CALLED ON NULL INPUT SECURITY INVOKER;

ERROR:  syntax error at or near "error"