On Apr 27, 2007, at 7:47 AM, Lachlan Deck wrote:
> On 27/04/2007, at 11:53 PM, Mike Kienenberger wrote:
>
>> Not sure how Entity Modeler does it, but Cayenne Modeler has a
>> checkbox that you can use to apply the locking/non-locking state to
>> every attribute of every entity.
>
> Entity Modeler (and EOModeler for that matter) has the option per
> attribute.
>
>> As for full optimistic locking (which is what you're doing if you
>> lock
>> by every attribute), the advantage is that you only have an
>> optimistic
>> locking failure if your current data state doesn't match the actual
>> data state in the database.
>
> There are just some attributes where such comparisons are
> unwarranted. e.g., BLOBs, and so forth.
Those are the exception, not the rule.
>> Ie, you read in your data, other processes make net efffect noop
>> changes to the data, and then you write out your data without any
>> locking exception.
>>
>> This also means that you don't have to maintain a version
>> attribute or
>> a last modified attribute for every table since the locking is based
>> on actual data values and not an arbitrary locking column in the
>> table.
>
> Sure. But the modified attribute also provides information for us.
> When present it seems to me to be the only necessity for locking
> (so long as you always update it prior to commit).
>
> Anyway this bug report was not about the reasons for choosing a
> certain approach (as that can depend on the particular application)
> but that there is a need to minimise the tool getting in the way.
IIRC, your request was to make them all default to not locked. For
me, and I suspect most others, that would make more work for us as we
seldom use the modified attribute. Even when I do use it, I don't do
so on all entities.
My 2 cents.
Chuck
> as an aside, and the reason why this bug report was lodged, was
> especially because I found that the more entities I added to the
> model the slower Entity Modeler was, with all the notifications and
> whatever it was doing in the background (I suppose verifying the
> model with every action). Thus, little things like this became
> increasingly irritating as it was just another thing that slowed
> the process down for modelling the entities.
>
> e.g., Clicking on the "Add new attribute" button five times in a
> row would take longer than 5 seconds to populate. Beach-ball city
> after a while... and clicking each of the attributes locking to
> untick the ones I wanted unticked, took too long also. Too much
> mouse clicking.
>
> All in all, I'm all for making stuff like this a preference.
>
> Over and out :-)
>
> with regards,
> --
>
> Lachlan Deck
>
>
>
>
--Practical WebObjects - for developers who want to increase their overall knowledge of WebObjects or who are trying to solve specific problems. http://www.global-village.net/products/practical_webobjects
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