Can I directly define a trigger in all_triggers table on a table?

Insert into employee ( employeeId, someColumn, someOtherColumn )
  Select 2, someColumn, someOtherColumn
  From employee
  Where employeeId=1

CREATE OR REPLACE TRIGGER  "DEFAULT_LOG_ENTRY" AFTER insert on "MAIN_APEX"
for each row 
 begin
  insert into apex_logs (log_entry, log_date, circulation,
                         main_pk_ref, techwriter)
  values ('This log page was established. Actions and communcations are captured from this date and time onward.'
         , sysdate
         , 'External'
         , :new.main_pk
         , :new.TECHWRITER);
 end;

CREATE OR REPLACE FUNCTION insert_tsttbl1_hourbase() RETURNS TRIGGER AS $$
BEGIN
    RAISE NOTICE 'Hi...%', NEW;
    Execute 'set search_path to ' || TG_TABLE_SCHEMA|| '';
    INSERT INTO tsttbl1_hour0 values (NEW.*);
    RETURN NULL;
END;
$$ LANGUAGE plpgsql;

SELECT *
FROM Table_b
WHERE A_id IN (SELECT A_Id
               FROM Table_b
               WHERE LENGTH(Value) = 4);

╔══════╦═══════╗
║ A_id ║ Value ║
╠══════╬═══════╣
║    3 ║ Goat  ║
║    3 ║ Cow   ║
╚══════╩═══════╝