This is a private place to put those AS features that are used
by every component. Nowadays we cherry-pick individual files
wherever they are used, but that it is not worth the effort
for stuff that is going to be loaded for sure sooner or later,
like blank?, autoload, concern, etc.

zero and the new value is not a string.

Before this commit this was the behavior

r = Review.find_by_issue(0)
r.issue
=> 0
r.changes
=> {}
r.issue = 0
=> 0
r.changed?
=> true
r.changes
=> {"issue"=>[0,0]}

Fixes #7237

Conflicts:
	activerecord/CHANGELOG.md

This can be used to get a Relation from an association.

Previously we had a #scoped method, but we're deprecating that for
AR::Base, so it doesn't make sense to have it here.

This was requested by DHH, to facilitate code like this:

    Project.scope.order('created_at DESC').page(current_page).tagged_with(@tag).limit(5).scoping do
      @topics      = @project.topics.scope
      @todolists   = @project.todolists.scope
      @attachments = @project.attachments.scope
      @documents   = @project.documents.scope
    end

This makes it easier to see what the documentation refers to.

It also means that we are not doing unnecessary work for delegations
that have no args / splats / block / etc.

This doesn't change the exernal behavior, but it moves some code around
to where I think it properly belongs.

This method explicitly loads the records and then returns `self`.

Rather than deciding between "do I want an array or a relation?",
most people are actually asking themselves "do I want to eager load
or lazy load?" Therefore, this method provides a way to explicitly
eager-load without having to switch from a `Relation` to an array.

Example:

    @posts = Post.where(published: true).load

This reverts commit 3803fcce.

Conflicts:
	activerecord/CHANGELOG.md

It will be deprecated only in 4.0, and removed properly in 4.1.

Move the logic for validation check to the same method, and cache
dependent option in a variable to reuse inside the dependency
configuration methods instead of relying on the options hash.

    User.order("name asc").order("created_at desc")
    # SELECT * FROM users ORDER BY created_at desc, name asc

This also affects order defined in `default_scope` or any kind of associations.

update_column was suggested as replacement of update_attribute at the
last release of 3-2-stable, so deprecating it now will confuse the
users.

See the comment in the file activerecord/lib/active_record.rb
added by this patch for the rationale.

This require makes the dependency even more clear.
In particular we are eager loading the session
store but that does not work if AR is used
outside Rails, this patch is preliminary work
in fixing #7160.

This reverts commit 14fc8b34.

Reason: we need to discuss a better path from this removal.

Conflicts:
	activerecord/lib/active_record/reflection.rb
	activerecord/test/cases/base_test.rb
	activerecord/test/models/developer.rb

to address ORA-01400 errors with Oracle enhanced adapter.

The original commit 3c0bf043 requires :json_data_empty attribute
has empty string OR null, then setting `:default => ""` is enough.

It has been moved to active_record_deprecated_finders.

Use #to_a instead.

It doesn't serve much purpose now that ActiveRecord::Base.all returns a
Relation.

The code is moved to active_record_deprecated_finders.

Previously it returned an Array.

If you want an array, call e.g. `Post.to_a` rather than `Post.all`. This
is more explicit.

In most cases this should not break existing code, since
Relations use method_missing to delegate unknown methods to #to_a
anyway.

`:rails_env` tasks is not needed in all the tasks that depends of
`load_config`, only in the tasks that uses `Rails.env`.

Since `:rails_env` task set the `Rails.env` to be "development" if it is
not set we don't need the `||` statements too

Fix #7175.

Conflicts:
	activerecord/lib/active_record/railties/databases.rake

to address ORA-01400 errors with Oracle enhanced adapter.

Issue #4856 had been fixed and tested with
the attribute `:null => false, :default => ""`.
Now `:null => false` attribute is not necessary to test this issue.

Moved logic from class_of_active_record_descendant(class) to the
base_class method. This method was confusing because it required
an argument, but that argument was 'self'.

Moved base_class tests to inheritance_test.rb and added some test
coverage for some untested cases.

Fixed markdown code indenting

Related to #7164

Looks like the last one; thanks!

to make store works all database adapters.

Closes #1190