| For most of my attributes, last in wins will be fine.
Would like to avoid SQL as there are a lot of fairly complicated computations being performed so really want to stick with Java for that.
Jeff
On Mar 18, 2016, at 1:02 PM, Philippe Rabier < email@hidden> wrote:
Jeff, if you remove the lock, you have a risk to get a write-write conflict, aka a write replaced by another. It’s maybe not a big deal. I don’t know.
Another solution, if you are sure your background db process is the only one to modify an attribute, is to use raw sql to update the column you want to modify.
Philippe On 18 mars 2016, at 17:42, Jeff Schmitz < email@hidden> wrote:
Thanks Chuck, Yep, I understand the issue with inconsistent data, but most of my attributes are not semantically dependent on other attributes in that way If that’s all the locks are guarding against I’ve got some lock trimming to do.
On Mar 18, 2016, at 11:11 AM, Chuck Hill < email@hidden> wrote:
Hi Jeff,
Yes, if a column is not marked as locking, then it won’t appear in the WHERE clause.
The danger is that you might save changes that are inconsistent with what the database has stored in the columns that you are not locking on. As a contrived example, consider the update below changing Bob to Robert. If you don’t lock on first and last
name, some other process might have updated both names to John Edwards. Your update will now change the name to Robert Edwards. You need to look at your data and see where that might matter and where it does not.
Chuck
I’m starting to get some optimistic column locking failures during background db processing soI’m trying to grasp conditions under which I don’t need to lock a column (i.e. put the little lock symbol in EOModeler)
If I have a column in a table that I know is not updated (i.e. changed) by any client except form my personal administrative page, can I get away without locking that column? On unlocked columns is there any where clause checks such as shown
below before that column is updated? If not, this should stop the locking errors, right? Any other dangers with this?
update Person set FirstName = 'Robert' where PersonID = 123 and FirstName = 'Bob' and LastName = 'Roberts'
Finally, to make this change Is it as simple as unchecking the column and redeploying my EOModel file?
Thanks!
Jeff
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