Re: ADO and Locking

From: Jan Hyde <StellaDrinker@xxxxxxxxxxxxxxxxxxx>
Date: Tue, 03 Oct 2006 11:59:34 +0100

John <John@xxxxxxxxxxxxxxxxxxxxxxxxx>'s wild thoughts were
released on Fri, 29 Sep 2006 12:03:02 -0700 bearing the
following fruit:

I use VB6/ADO/SQL Server 2000.

I have a table (MachineConfig) that controls two machines. When the machine
(ID = 1) starts, it will create it's own configuration data into the table,
then "select * from MachineConfig where MachineID = 1" into a ADO recordset,
then process and update the configuration through the recordset. At the same
time, the other machine needs to start and do the same thing. However, it
cannot start at all.

Is the table locked when one machine starts? The recordset is just a subset
of the table, why is the whole table locked? Is there any way I can lock just
a row?

You need to give the table an index so that the database can
perform row level locking.

If there are no indexes then you pretty much give it no
option other than lock the whole table.

Jan Hyde (VB MVP)

--
Polarize: What penguins see with (Hershy)

.

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