Trigger: Only raise error if related record was NOT created between now and last Sunday

Question

I have a trigger that prevents inserts into a DELETES table under certain conditions:

CREATE OR REPLACE TRIGGER D202574_custom
BEFORE INSERT ON D202574
FOR EACH ROW
DECLARE 
    v_upd_row NUMBER;
BEGIN
    SELECT COUNT(1) INTO v_upd_row 
    FROM A202574
    WHERE objectid = :new.sde_deletes_row_id
    AND sde_state_id = :new.deleted_at;

    IF v_upd_row = 0 THEN
         raise_application_error(-20001, 'Deleting has been disabled via a custom trigger.');
    END IF;
END ;

---

I want to enhance the trigger so that it only raises an error if the related record in the base table was NOT created between now and last Sunday at 11:59 PM.

• The relationship would be based on the OBJECTID column.

This is what the base table looks like:

CREATE TABLE A_TEST_BASE_TABLE
(
  OBJECTID          INTEGER NOT NULL,
  SHAPE             SDE.ST_GEOMETRY,
  CREATED_USER      NVARCHAR2(255),
  CREATED_DATE      TIMESTAMP(6),   --<<-- the relevant field
  LAST_EDITED_USER  NVARCHAR2(255),
  LAST_EDITED_DATE  TIMESTAMP(6)
)

What would it take to do this?

Answer 1

If I understood you correctly, then see if this helps:

• select created_date from that table
• check if it is lower than previous Sunday's 23:59
  • why? Because I presume that it can't be created in the future

How to find that moment in time? One option is to use NEXT_DAY function which returns the "next" Sunday, but - if you subtract 7 (days) from it, you ge previous Sunday which is what you want. Then add 23:59 to the truncated date value and that's it.

Words into code:

SQL> select to_char(sysdate, 'dd.mm.yyyy hh24:mi, day') right_now,
  2    trunc(next_day(sysdate, 'sunday') - 7) + 23/24 + 59/(24*60) previous_sunday_2359
  3  from dual;

RIGHT_NOW                                              PREVIOUS_SUNDAY_235
------------------------------------------------------ -------------------
29.08.2020 22:39, saturday                             23.08.2020 23:59:00

SQL>

Put into the trigger:

CREATE OR REPLACE TRIGGER D202574_custom
BEFORE INSERT ON D202574
FOR EACH ROW
DECLARE 
    v_upd_row  NUMBER;
    v_cre_date date;
BEGIN
    SELECT COUNT(1) INTO v_upd_row 
    FROM A202574
    WHERE objectid = :new.sde_deletes_row_id
      AND sde_state_id = :new.deleted_at;
      
    SELECT MIN(a.created_date) INTO v_cre_date
    FROM a_test_base_table a
    WHERE a.objectid = :new.sde_deletes_row_id;
      
    IF v_upd_row = 0 AND
       v_cre_date < trunc(next_day(sysdate, 'sunday') - 7) + 23/24 + 59/(24*60)
    THEN
       raise_application_error(-20001, 'Deleting has been disabled via a custom trigger.');
    END IF;
END;

Answer 2

This is the trigger that I ultimately ended up using:

create or replace trigger V202577_DELETE_custom
    before insert
    on D202577
    for each row
declare
    v_upd_row       number;
    v_cre_date_row   number;
begin
    select 
        count (1)
        into v_upd_row
        from A202577
     where
        objectid = :new.sde_deletes_row_id
        and sde_state_id = :new.deleted_at;

    select 
        count (1)
        into v_cre_date_row
    from 
        a_test_table a
     where
        a.objectid = :new.sde_deletes_row_id
        and a.created_date < trunc(next_day (sysdate - 6, 'monday'));

    if v_upd_row = 0 and v_cre_date_row > 0
    then
        raise_application_error ( -20001, 'Deleting has been disabled via a custom trigger.');
    end if;
end;