Re: Visibility of committed changes

Vlad is correct - there are some points at which the manuals are lacking in precision. The fact that you think the manuals are right is actually a demonstration of how easy it is to confuse the terms "statement", "query" and "transaction".

Session A: (me)
create table t1 (n1 number);

Session B:
insert into t2 values(1); -- starts a transaction before "me"

Back to session A
insert into t2 values(2);
commit;

Back to session B
select * from t1;
N1

---
  1
  2


Session B can see the value from the
transaction committed by session A, even
though the transaction in Session A did
not start before the transaction in session B.


--
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Jonathan Lewis
http://www.jlcomp.demon.co.uk

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Justin Cave wrote in message
<233b7a65.0301110306.5400679d_at_posting.google.com>...
>"vlad" <bulk_at_sfatcu.com> wrote in message
news:<YaQT9.520599$GR5.237852_at_rwcrnsc51.ops.asp.att.net>...


>> Hello. I've been reading up on Oracle lately and I find something

quite


>> strange in the "Concepts" manual. This is what they claim:




>>




>> -------------------------------------------------------------------

>> The changes made by the SQL statement(s) of your transaction become

>> permanent and visible to other users only after your transaction

has


>> been committed. Only other users' transactions that started after

yours


>> will see the committed changes.

>> -------------------------------------------------------------------

>

>
>The Oracle documentation is absolutely correct.  How are you doing
>your testing?  My guess is that you've turned on autocommit, so each
>statement is a transaction.
>
>Justin Cave
>