Rails - Jan 2012 - AR update / create pattern: is there an easier way?

I find myself writing the following frequently:

    r = MyActiveRecord.where(:attr1 => cond1, :attr2 => cond2, ...)
    r.exists? ? r.first : r.create

... which has the effect of returning an instance of MyActiveRecord if
all the conditions are met, or creating one if it doesn''t.  A variant
of
this:

    c = MyActiveRecord.new(:attr1 => val1, :attr2 => val2, ...)
    r = MyActiveRecord.where(:attr1 => c.attr1, :attr2 => c.attr2, ...)
    c.save! unless r.exists?

... which has the effect of writing c to the db only if it is unique
across the given attributes.

Question: Do either of these forms replicate functionality already
provided by ActiveRecord?  (I know about the find_or_create dynamic
methods, but those get unwieldy with more than two attributes.)  Is
there a cleaner or more idiomatic way?

- ff

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On 4 January 2012 20:25, Fearless Fool
<lists-fsXkhYbjdPsEEoCn2XhGlw@public.gmane.org>
wrote:
> I find myself writing the following frequently:
>
>    r = MyActiveRecord.where(:attr1 => cond1, :attr2 => cond2, ...)
>    r.exists? ? r.first : r.create
You want to look at the create_or_update_by_id and
find_or_initialize_by_id methods :-)

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