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From "Danny" <danny.gallag...@gainergroup.com>
Subject RE: Select records that are not locked?
Date Fri, 06 Jan 2006 17:11:16 GMT
What I was after was a way to build a list of transactions that are
available to edit for a user.

 

What I don't want in the list is any transactions that are currently being
edited by another user.

 

I think that I am back to comparing the last update timestamp on the row,
the first timestamp is pulled from the database when the

user selects the transaction and then on the update of the transaction
adding the last update that was pulled to the where clause, if I get an
exception

that that row doesn't exist, it is because it was updated by another user in
the time since this user selected it for edit.

 

Danny Gallagher

The Gainer Group

6525 The Corners Parkway

Suite 215

Norcross Ga, 30092

 

 

  _____  

From: Craig.Russell@Sun.COM [mailto:Craig.Russell@Sun.COM] 
Sent: Thursday, January 05, 2006 6:59 PM
To: Derby Discussion
Subject: Re: Select records that are not locked?

 

Hi Danny,

 

On Jan 5, 2006, at 11:14 AM, Danny wrote:





Is there a way on a select statement to select all rows that match the where

clause criteria, except for any rows that are locked?

 

I hope not. That's not the way I understand databases are supposed to work.
The result of a query is not dependent on the state of the internal
exclusion mechanisms.

 

Perhaps what you want is "dirty read" (isolation level 0) where the select
statement is not blocked by any locks...

 

Craig



 

Danny Gallagher

The Gainer Group

6525 The Corners Parkway

Suite 215

Norcross Ga, 30092

 

 

 

 

 

 

Craig Russell

Architect, Sun Java Enterprise System http://java.sun.com/products/jdo

408 276-5638 mailto:Craig.Russell@sun.com

P.S. A good JDO? O, Gasp!

 


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