On Wed, 2004-02-11 at 20:26, Jos� R�mulo El�as Contreras wrote:
> SAPDB locks the table when I modified only one row of this table?
> How Can I read and modify the rows that the transaction is NOT
> modified?
The behaviour you are expecting is called MVCC (multi version
concurrency control) and is not implemented by maxdb. MVCC is
implemented by oracle and postgresql.
You are not blocking on a table lock, but the queries from your second
transaction are hitting one of the row locks taken by first tx. AFAIK
MVCC support is not planned.
TX1 | TX2
update t set val=3 where pk=5 |
| update t set val=4 where pk=6
commit | commit
Here, if pk is t's primary key, the update in tx2 will not block.
TX1 | TX2
update t set val=3 where pk=5 |
| update t set val=4 where pk>4
commit |
| commit
In this case tx2 will block on the update because it waits for the
rowlock on the tuple with pk=5
--
MaxDB Discussion Mailing List
For list archives: http://lists.mysql.com/maxdb
To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
