Oracle 18c

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create table integrations (bck_id, int_id) as
select 1, 1 from dual;
1 rows affected

create table int_modules (int_id, mod_id) as
select 1, 1 from dual;
1 rows affected

create table backends (bckm_id, bck_id) as
select 1, 1 from dual;
1 rows affected

create table routing_sequences (bckm_id) as
select 1 from dual;
1 rows affected

create table modules (int_id, mod_lev_integration, mod_id, mod_table) as
select 1, 1, 1, 'TABLE_A' from dual
1 rows affected

create or replace TRIGGER "TU_INTEGRATIONS" BEFORE UPDATE ON INTEGRATIONS
    REFERENCING NEW AS NEW OLD AS OLD
    FOR EACH ROW
DECLARE
    bckId   INTEGER;
    SQLBody VARCHAR2(500);
    tableName VARCHAR2(100);
BEGIN
    IF :OLD.BCK_ID<> :NEW.BCK_ID THEN
        DELETE FROM INT_MODULES  im
        WHERE  im.INT_ID = :NEW.INT_ID AND NOT
            EXISTS
                (SELECT 1 FROM  (SELECT BCKM_ID FROM BACKENDS WHERE BACKENDS.BCK_ID = :NEW.BCK_ID)  b JOIN  ROUTING_SEQUENCES rs
                                                                                                            ON rs.BCKM_ID = b.BCKM_ID);
    END IF;

    FOR item IN (
        SELECT MOD_TABLE
        FROM MODULES  m
        WHERE MOD_LEV_INTEGRATION = 1
          AND NOT EXISTS (SELECT 1 FROM INT_MODULES imi WHERE imi.INT_ID = :NEW.INT_ID AND imi.MOD_ID = m.MOD_ID)
        ) LOOP
            SQLBody := 'DELETE FROM ' ||  item.MOD_TABLE || ' WHERE INT_ID = ' || TO_CHAR(:NEW.INT_ID);
            EXECUTE IMMEDIATE SQLBody;

        END LOOP;

END TU_INTEGRATIONS;
/
select * from user_errors;
create table table_a (int_id number);
update integrations set int_id = 2;
1 rows affected

rollback;
alter table table_a rename column int_id to dummy;
update integrations set int_id = 2;
ORA-00904: "INT_ID": invalid identifier
ORA-06512: at "FIDDLE_PKYIDVFUMYZGZAGMJLGD.TU_INTEGRATIONS", line 21
ORA-06512: at "FIDDLE_PKYIDVFUMYZGZAGMJLGD.TU_INTEGRATIONS", line 21
ORA-04088: error during execution of trigger 'FIDDLE_PKYIDVFUMYZGZAGMJLGD.TU_INTEGRATIONS'