Oracle 21c

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select * from V$VERSION;


BANNER
BANNER_FULL
BANNER_LEGACY
CON_ID


Oracle Database 21c Express Edition Release 21.0.0.0.0 - Production
Oracle Database 21c Express Edition Release 21.0.0.0.0 - Production
Version 21.3.0.0.0
Oracle Database 21c Express Edition Release 21.0.0.0.0 - Production
0


create table t (id int, val int, modified timestamp default systimestamp)
create or replace trigger trigg_on_t  
before update on t for each row enable  
begin  
    :new.modified := systimestamp;  
end;
/
insert into t (id, val) values (1, 1)
1 rows affected

commit
select * from t


ID
VAL
MODIFIED


1
1
28-AUG-23 21.50.00.727243


merge into t  
using (  
    select 1 id, 10 val, 1 flag from dual  
) s on (t.id = s.id)  
when matched then  
    update set t.val=s.val  
    delete where s.flag=1
ORA-30926: unable to get a stable set of rows in the source tables

merge into t  
using (  
    select 1 id, 1 val, 1 flag from dual  
) s on (t.id = s.id)  
when matched then  
    update set t.val=s.val, modified=systimestamp    
    delete where s.flag=1
1 rows affected

rollback
alter trigger trigg_on_t disable
merge into t  
using (  
    select 1 id, 1 val, 1 flag from dual  
) s on (t.id = s.id)  
when matched then  
    update set t.val=s.val  
    delete where s.flag=1
1 rows affected