How to block an application for example TOAD in oracle

How to block an application for example TOAD in oracle

---DIRECTORY CREATION

CREATE OR REPLACE DIRECTORY ADMIN  as '/apps/app/oracle/product/9201/network/log/' ;

-in the above command  you need to replace the path with your  listener.log   location

---EXTERNAL TABLE CREATION

create table application_check
(    logon_date     varchar2(100),
    program     varchar2(400),
    protocol     varchar2(100),
    host_name     varchar2(15))
    organization     external
    (type         oracle_loader
    default     directory     admin
    access         parameters
    (records     delimited     by newline
    badfile     'test.bad'
    discardfile     'test.dis'
    logfile     'test.log'
    fields         terminated     by "*"
    (
    LOGON_DATE     CHAR,
    PROGRAM     CHAR,
    PROTOCOL     CHAR,
    HOST_NAME     CHAR)
    )
    LOCATION    ('listener.log')
    )
    REJECT LIMIT UNLIMITED;

---VIEW CREATION

create or replace view application_view AS
    select     substr(program,44,65) program ,
        substr(protocol,31,15) ipaddress,
        TO_DATE(SUBSTR(LOGON_DATE,1,19),'DD-MON-YYYY HH24:MI:SS') LOGON_DATE
    FROM      application_check
    where     program is not null
    and     LOGON_DATE not like '%TIMESTAMP%';

--
create or replace trigger application_login_check
after logon on database
declare
x     number;
begin
    select     count(1) into x
    from     dotsoft_application_view a
    where    (upper(a.program) like '%TOAD%'
    or     upper(a.program) like '%IFBLD%'
    or     upper(a.program) like '%IFBLD%'
    or     upper(a.program) like '%RWBLD%'
    or     upper(a.program) like '%DLLHOST%')
    and     (sysdate-a.logon_date)*24*60*60 < 60;

    if x>0 then
        raise_application_error(-20001,'You are not authorized');
    end if;
end;
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