Using dbms_lob in trigger 10gR2

Question

Hello,
I'm trying to read from a clob using dbms_lob in my trigger and assigning the value to a variable. My trigger is compiling fine, but it doesn't seem to be working.
I'm using 10gR2. Am I misunderstanding how to read from/assign to a variable in a trigger?
Line from trigger code:
v_serial_start := dbms_lob.instr(:new.search_xml_clob,'serial=') + 8;
Thanks,
Mimi

Answer 1

Here's a quick example that works fine for me....
ME_XE?create table clobberin_tyme
  2  (
  3     some_column    number,
  4     variable_value number default 0,
  5     some_clob      clob default empty_clob()
  6  );
Table created.
Elapsed: 00:00:03.98
ME_XE?
ME_XE?
ME_XE?create or replace trigger clobberin_tymeT01
  2  before insert or update on clobberin_tyme
  3  for each row
  4  declare
  5     v_serial_start    number;
  6  begin
  7
  8     v_serial_start       := dbms_lob.instr(:new.some_clob,'serial=') + 8;
  9
10     :new.variable_value  := v_serial_start;
11
12  end;
13  /
Trigger created.
Elapsed: 00:00:02.62
ME_XE?
ME_XE?
ME_XE?insert into clobberin_tyme (some_column) values (1);
1 row created.
Elapsed: 00:00:00.31
ME_XE?
ME_XE?select * from clobberin_tyme;
       SOME_COLUMN     VARIABLE_VALUE SOME_CLOB
                 1                  8
1 row selected.
Elapsed: 00:00:00.17
ME_XE?
ME_XE?update clobberin_tyme
  2     set   some_column = 2,
  3           some_clob = 'hello world serial= coco puffs, i am cucu for them';
1 row updated.
Elapsed: 00:00:00.25
ME_XE?
ME_XE?select * from clobberin_tyme;
       SOME_COLUMN     VARIABLE_VALUE SOME_CLOB
                 2                 21 hello world serial= coco puffs, i am cucu for them
1 row selected.
Elapsed: 00:00:00.01