<div dir="ltr">Using the UPDATE WHERE statement you described is referred to as optimistic locking. [1]<div><br></div><div><a href="https://docs.jboss.org/jbossas/docs/Server_Configuration_Guide/4/html/The_CMP_Engine-Optimistic_Locking.html">https://docs.jboss.org/jbossas/docs/Server_Configuration_Guide/4/html/The_CMP_Engine-Optimistic_Locking.html</a><br>

</div></div><div class="gmail_extra"><br><br><div class="gmail_quote">On Wed, Jul 30, 2014 at 10:30 AM, Jay Pipes <span dir="ltr"><<a href="mailto:jaypipes@gmail.com" target="_blank">jaypipes@gmail.com</a>></span> wrote:<br>

<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div class="">On 07/30/2014 10:05 AM, Kevin Benton wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
i.e. 'optimistic locking' as opposed to the 'pessimistic locking'<br>
referenced in the 3rd link of the email starting the thread.<br>
</blockquote>
<br></div>
No, there's no locking.<br>
<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div class="">
On Wed, Jul 30, 2014 at 9:55 AM, Jay Pipes <<a href="mailto:jaypipes@gmail.com" target="_blank">jaypipes@gmail.com</a><br></div><div class="">
<mailto:<a href="mailto:jaypipes@gmail.com" target="_blank">jaypipes@gmail.com</a>>> wrote:<br>
<br>
    On 07/30/2014 09:48 AM, Doug Wiegley wrote:<br>
<br>
            I'd have to look at the Neutron code, but I suspect that a<br>
            simple<br>
            strategy of issuing the UPDATE SQL statement with a WHERE<br>
            condition that<br>
<br>
<br>
        I¹m assuming the locking is for serializing code, whereas for<br>
        what you<br>
        describe above, is there some reason we wouldn¹t just use a<br>
        transaction?<br>
<br>
<br>
    Because you can't do a transaction from two different threads...<br>
<br>
    The compare and update strategy is for avoiding the use of SELECT<br>
    FOR UPDATE.<br>
<br>
    Best,<br>
    -jay<br>
<br>
<br>
<br></div>
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<br>
<br>
<br>
<br>
<br>
--<br>
Kevin Benton<br>
<br>
<br>
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<br>
</div></blockquote><div class="HOEnZb"><div class="h5">
<br>
<br>
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</div></div></blockquote></div><br><br clear="all"><div><br></div>-- <br><div>Kevin Benton</div>
</div>