Re: can an update operation not been hooked if record has beed locked?

The concept is that you select the rows for update and then update them. 2 steps.
Jim
"PanTao" <pantao_fz_at_21cn.com> wrote in message news:f76a630f.0204300520.59c7ecf2_at_posting.google.com...
> Hello, all
>
> I found that there is nowait option for "select for update", "lock
 table",
> I would like to know if there is nowait option for update? Or is there a
 nowait
> option for a tranacation?
>
> also I found a pl/sql script from The Oracle (tm) Users' Co-Operative FAQ
> to identify all locked rows in a table. I would like to know what does the
> _at_nowait and nowait_cond mean. Sorry I know little about pl/sql and I just
> check the document in a hurry and find no clue. The script is below:
>
> UT1> set echo on
> UT1> _at_nowait
> UT1> set serveroutput on
> UT1> declare
> 2 v_rowid rowid ;
> 3 v_fld1 marktest.fld1%type;
> 4 v_fld1b marktest.fld1%type;
> 5 --
> 6 cursor c_fulltable is
> 7 select rowid
> 8 ,fld1
> 9 from marktest
> 10 order by fld2;
> 11 --
> 12 nowait_cond exception ;
> 13 pragma exception_init(nowait_cond,-00054) ;
> 14 --
> 15 begin
> 16 open c_fulltable;
> 17 loop
> 18 fetch c_fulltable into v_rowid, v_fld1;
> 19 exit when c_fulltable%notfound;
> 20 begin
> 21 select fld1
> 22 into v_fld1b
> 23 from marktest a
> 24 where a.rowid = v_rowid
> 25 for update nowait;
> 26 dbms_output.put_line('Got row '||v_fld1);
> 27 exception
> 28 when nowait_cond then
> 29 dbms_output.put_line('Row is locked '||v_fld1);
> 30 end;
> 31 end loop;
> 32 close c_fulltable;
> 33 end;
> 34 /
> Row is locked one
> Got row two
> Row is locked three
> Got row four
> Row is locked five
>
> Anyone know about it? Many thanks!
> PanTao
Received on Tue Apr 30 2002 - 15:56:50 CEST