Ruby on Rails Friday, July 7, 2017

On 7 July 2017 at 15:25, Alex Morton <> wrote:
> I have a model called Dataset which registers an after_save callback to do
> some work when its name attribute has changed. This callback is manipulating
> a DatasetLink model but the association between the two is through another
> model called Attribute.
> The scenario I'm hoping to come to an explanation for is this:
> Within the after_save callback, the immediate reference to the Dataset model
> that's changing returns true for name_changed? and changed?. However, when
> traversing the association to a DatasetLink record, the link's reference to
> the dataset has the new value for the name but it doesn't register the
> dataset as being changed nor the name being changed. It just has the new
> name.

Since traversing the associations probably means that the record will
be re-read from the database it is correct that the changed flags are
not set (for that in-memory record), as the value of name in the
record in memory has not changed since it was read.


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