in your case is "tinystring" always <32767?
Your time is going to be wasted in the FORALL part looking up all the temporary lobs you've made.
you'd find better performance with inserts in the for each row part :
eg on my test system with your lob trigger:
SQL> insert into target_Table select 'ABC' from dual connect by level <= 10000;
10000 rows created.
Elapsed: 00:00:10.49
vs having the trigger as:
SQL> CREATE OR REPLACE TRIGGER mdhl_basic_trigger
2 before INSERT OR UPDATE OR DELETE ON target_table for each row
3 declare
4
5 my_bgroup VARCHAR2(3);
6
7 v_timer2 number := 0;
8 v_timer number;
9 BEGIN
10
11 IF INSERTING OR UPDATING THEN
12 my_bgroup := :NEW.BGROUP;
13 ELSE
14 my_bgroup := :OLD.BGROUP;
15 END IF;
16
17 INSERT INTO log_table VALUES(my_bgroup, 'BASIC_MDHL', current_timestamp, 'TinyString');
18
19 END mdhl_basic_trigger;
20 /
SQL> insert into target_Table select 'ABC' from dual connect by level <= 10000;
10000 rows created.
Elapsed: 00:00:01.18
if you KNOW your strings are always <32k you can keep the forall to get that speed boost if you create your trigger as:
SQL> CREATE OR REPLACE TRIGGER mdhl_basic_trigger_compound
2 FOR INSERT OR UPDATE OR DELETE ON target_table
3
4 COMPOUND TRIGGER
5
6 type events_rec is record (BGROUP VARCHAR2(3),
7 TABLE_NAME VARCHAR2(255) ,
8 EVENT_TS TIMESTAMP (7),
9 EVENT_RAW varchar2(32767));
10 TYPE EVENTS_HIST IS TABLE OF events_rec INDEX BY PLS_INTEGER;
11 coll_events_hist EVENTS_HIST;
12 ctr PLS_INTEGER := 0;
13 my_bgroup VARCHAR2(3);
14
15 v_timer2 number := 0;
16 v_timer number;
17 BEFORE EACH ROW IS
18 BEGIN
19
20 IF INSERTING OR UPDATING THEN
21 my_bgroup := :NEW.BGROUP;
22 ELSE
23 my_bgroup := :OLD.BGROUP;
24 END IF;
25
26 ctr := ctr + 1;
27 coll_events_hist(ctr).BGROUP := my_bgroup;
28 coll_events_hist(ctr).TABLE_NAME := 'BASIC_MDHL';
29 coll_events_hist(ctr).EVENT_TS := current_timestamp;
30 coll_events_hist(ctr).EVENT_RAW := 'TinyString';
31
32 END BEFORE EACH ROW;
33
34 AFTER STATEMENT IS
35 BEGIN
36 v_timer := dbms_utility.get_time;
37 FORALL counter IN 1 .. coll_events_hist.count()
38 INSERT INTO log_table VALUES coll_events_hist(counter);
39 v_timer2 := v_timer2 + (dbms_utility.get_time - v_timer);
40 dbms_output.put_line(v_timer2/100);
41 END AFTER STATEMENT;
42 END mdhl_basic_trigger_compound;
43 /
SQL> insert into target_Table select 'ABC' from dual connect by level <= 10000;
10000 rows created.
Elapsed: 00:00:00.39
i.e. defer the lob operation until the insert.