Greg Young's 2 day workshop July 21st 2011

[Adam Dymitruk]

Doing this from a laptop over a slow wifi. Bear with me, it should be faster once I get home. Please seed to help everyone.

Thanks!

Adam

[jmbeas]

Thanks Adam,

Is there any public URL so we can tweet it?

Regards,
JMB

http://jmbeas.es
http://twitter.com/jmbeas

>  GregYoung_CQRS_2011JUL21.torrent
> 20KViewDownload

[Sebastian Ganslandt]

Thanks a lot for sharing!

'Sebastian

On Jul 26, 12:03 am, Adam Dymitruk <adymit...@gmail.com> wrote:

>  GregYoung_CQRS_2011JUL21.torrent
> 20KViewDownload

[Roundcrisis]

yes, listening to it now
Andrea
www.roundcrisis.com

[João Bragança]

Even if we missed the class can we still donate

Sent from my Droid

[Greg Young]

Sure there has been a donation link on cqrsinfo.com for a long time
(there have only ever been two donations through it though, so maybe
people don't see it :))

Generally I find a worthy charity to give the donations to as well.
For the class its the SPCA

2011/7/26 João Bragança <joao...@braganca.name>:

--
Le doute n'est pas une condition agréable, mais la certitude est absurde.

[Adam Dymitruk]

This was my fault for sharing it publicly. So please do contribute
something to Greg's charity of choice. The good thing is that there
will be a lot more exposure to CQRS, I guess.

--
Adam

http://adventuresinagile.blogspot.com/
http://twitter.com/adymitruk/
http://www.agilevancouver.net/
http://altnetvan.grou.ps/

[Aleš Vojáček]

I'm sorry, I downloaded that screen cast, and this is for my education only.
I hope that this is not problem.

May be that my first question is some kind stupid, but what are normal
donations for that stuff?

My second question is, I like that push model which Greg said.
(inventory subsystem push to sales) but what if sales is down? It will
miss some messages from Inventory subsystem?
Another scenario is what if some messages are pushed from Inventory
subsytem to Sales and another are pushed from Sales to Inventory. This
can be source of another type of problems.

Thank you for your time especially for my first question. :-)
A.

[Greg Young]

Queue.. Either in the system directly or more likely with a guaranteed delivery transport like a message queue

[Aleš Vojáček]

Ok, but what if Sales pushes to Inventory event that something was
sold (Inventory have to process some logic say 1s) and before it was
processed some other wants to buy same product from sales. I have in
their db wrong number of that stuff because event was not pushed from
inventory yet.

I'm sorry for my rally bad english I hope that you can understand me :-)

A.

[Greg Young]

Eventual consistency. What happens if you call a webservice on the other to see if you cake sale in 2 threads?

Generally this is acceptable to some point where risk becomes more of a burden.

Btw in sales generally you would want to sell the item anyways especially a high value / profit item

[Greg Young]

Also it opens business concepts to developers / in the model. I can assure you the sales people sell anyways if they can :)

[Aleš Vojáček]

:-)
yup you are right but I do not now how it is in your country, but if I
have ERP system with accounting I have to have accounting in right
state in time, so I cannot have stock of items in minus numbers and
so. Accounting is source of truth. But you are right sales, marketing,
..... are the most. The shame is that accounting has to be in right
state in every situation.
May be that I'm missing something so I have to thing about that.
Eventual consistency is hard to think about for me, may be it is ok
between UI and domain, but between peaces of software it is hard to
think about (for me) .
A.

[Simon Harris]

FWIW, the example I really like is that of a bank ATM network. If the network is down, at least in Australia, ATMs will still dispense cash up to some pre-defined limit, even if that means my account goes in to the -ve.

In my very short experience with all this, I've seen nothing to suggest that there's anything wrong with pro-actively reading from an, allbeit possibly out-of-date, view and then dealing with the consequences of perhaps going -ve.

In an extreme case, do what I have done and run some view generation in process. It won't necessarily scale but for some problems it's just simpler.

My 2c worth.

[Greg Young]

Yes. And quantify business risk of having the stale data.

Do u have a citing on Australian ATMs?

[Simon Harris]

On 03/08/2011, at 9:45 AM, Greg Young wrote:

> Do u have a citing on Australian ATMs?

Not readily; it comes from personal experience :)

[Aleš Vojáček]

:-)

[Wayne Douglas]

I also downloaded this as I thought it was public domain, same as the
original greg young cqrs stuff.

If it's ok with you greg - i'd like to donate some money to the
Somalia crises: http://www.dec.org.uk/

Thank you

w://

--
Cheers,

w://

[Greg Young]

Sure no problem as many know I have quite an attachment to africa

[Colin Yates]

I am eagerly consuming as much info CQRS as I can find and the skillsmatter podcasts and cqrsinfo.com sites are excellent.  

My question is, is the attachment this thread is about legal (and ethical) to download.  If so, can somebody paste the original link please?

Col

[Greg Young]

Hey Colin, no worries. I think link is in the archive

[Colin Yates]

Excellent - cheers.

[Wayne Douglas]

just got a service unavailable trying to donate!!

f^&*ng Brittish Telecom!! (they run the donation site - if they used
cqrs this wouldn't happen! lolz)

--
Cheers,

w://

[Greg Young]

lol!