Why does activerecord optimistic locking work only once per row? -


Anyhow, I always get on Friday.

My first question was in relation to the same problem, but I can now narrow down a few things:

I am playing with this whole day, to understand it I am trying. I have a table with a lock_version column, which is specified: 

  add_column: jobs,: lock_version,: integer,: default = & gt; 0

And I do something like this: 

  foo = job.create! First = Job.find (foo.id) II = Job.find (foo.id)

I again confirm that the first and the second see the same object - identical to their ID And I see that line in the database using the mysql command-line tool. 

  first.some_attribute_field = 'first' second.some_attribute_field = 'second' first.save second.save

No problem yet I have an ActiveRecord: : I get the StaleObjectError exception correctly. However : 

  first = job.find (foo.id) second = job.fund (foo.id) first.some_attribute_field = 'first' second.some_attribute_field = 'Second' first. Second Savita

... and nothing happens. It has come to know that only once I treat the right (thrown exception), the first and the second of the lock_version is 0. After saving it first, it is not 0 again. What's on the earth?

I am using Ruby 1.8.6 and active record 2.2.2

thanks ...

When you first call, the value of" some_attribute_field "is already equal to" before ", activerecord knows it, so it does not update lock_version The DB did not increase. In the second trial, try to change the value for something other than "first" so that it is different from what is in DB.


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