[ci skip] Pluck loads the records but omits attributes

[AdityaBhutani]

Summary

Pluck Doc incorrectly states "Use #pluck as a shortcut to select one or more attributes without loading a bunch of records just to grab the attributes you want."

Instead It loads the rows but omits the extra attributes.

Updating the doc to be consistent with functionality of pluck.

[ghiculescu]

Hmm, what is incorrect about the statement? I think it’s written relative to loading all the records and then calling map to just get the attributes you want.

[AdityaBhutani]

Hey @ghiculescu. It says, "without loading bunch of Records" but instead it loads the respective records, only with selective attributes.

[ghiculescu]

I think "record" means initiatlising the Active Record objects. The rows are loaded from the database and they are type cast, but no AR objects are constructed. This is one of the things that makes pluck faster.

[AdityaBhutani]

Thanks. This makes sense now.
Do you suggest to make it more clear by restating it like "Use #pluck as a shortcut to select one or more attributes without loading a bunch of ActiveRecord objects just to grab the attributes you want."
Reason: People have earlier been confused by this here

[ghiculescu]

👍 yeah, I like that.

[AdityaBhutani]

Hey @ghiculescu, I had a concern related to test cases. There are many places where we have used map(&:id) where we should use pluck(:id) or ids. Would this change be considered superficial ?

[jonathanhefner]

"Active Record" needs a space. But, looking at the pick docs, what do you think about this alternative:

Suggested change

	# loading a bunch of ActiveRecord objects just to grab the attributes you want.
	# loading an entire record object per row.

Or even this one:

Suggested change

	# loading a bunch of ActiveRecord objects just to grab the attributes you want.
	# instantiating a model object per row.

[AdityaBhutani]

Second one looks perfect. Do you think we can use Active Record instead of model, because we also have Active Model.

[jonathanhefner]

Here, "model" refers to the "model" in model-view-controller, not Active Model.

Conversely, "Active Record" is a framework which defines many objects / classes, ActiveRecord::Base among them.

All in all, if you would prefer not to use the word "model", I would go with "entire record object".

[jonathanhefner]

Thank you, @AdityaBhutani!