Previously, executing an insert SQL in PostgreSQL with a command like this:
insert into articles(
number)
values(
5152
)
would not work because the adapter was unable to extract the correct articles table name.
This change was necessary because the whitelist wouldn't work.
It would be painful for users trying to update their applications.
This blacklist intent to prevent odd bugs and confusion in code that call mutator
methods directely on the `Relation`.
Using the name of an association in `where` previously worked only
if the value was a single `ActiveRecrd::Base` object. e.g.
Post.where(author: Author.first)
Any other values, including `nil`, would cause invalid SQL to be
generated. This change supports arguments in the `where` query
conditions where the key is a `belongs_to` association name and the
value is `nil`, an `Array` of `ActiveRecord::Base` objects, or an
`ActiveRecord::Relation` object.
# Given the Post model
class Post < ActiveRecord::Base
belongs_to :author
end
# nil value finds records where the association is not set
Post.where(author: nil)
# SELECT "posts".* FROM "posts" WHERE "posts"."author_id" IS NULL
# Array values find records where the association foreign key
# matches the ids of the passed ActiveRecord models, resulting
# in the same query as Post.where(author_id: [1,2])
authors_array = [Author.find(1), Author.find(2)]
Post.where(author: authors_array)
# ActiveRecord::Relation values find records using the same
# query as Post.where(author_id: Author.where(last_name: "Emde"))
Post.where(author: Author.where(last_name: "Emde"))
Polymorphic `belongs_to` associations will continue to be handled
appropriately, with the polymorphic `association_type` field added
to the query to match the base class of the value. This feature
previously only worked when the value was a single `ActveRecord::Base`.
class Post < ActiveRecord::Base
belongs_to :author, polymorphic: true
end
Post.where(author: Author.where(last_name: "Emde"))
# Generates a query similar to:
Post.where(author_id: Author.where(last_name: "Emde"), author_type: "Author")
db:test:clone and db:test:prepare use
ActiveRecord::Base. configurations, so we need to load the rails
environment, otherwise the config wont be in place.
For PG adapters with custom expression and grouped result
of aggregate functions have not found correct column type
for it. Extract column type from query result.
Closes: #13230
Example: Given you have a comments model with a polymorphic commentable
association (e.g. books and songs) with the touch option set.
Every time you update a comment its commentable should be touched.
This was working when you changed attributes on the comment or when you
moved the comment from one book to another. However, it was not working
when moving a comment from a book to a song. This is now fixed.
Fixture files are passed through an ERB renderer before being read as
YAML. The rendering is currently done in the context of the main object,
so method definitons leak into other fixtures, and there is no clean
place to define fixture helpers.
After this commit, the ERB renderer will use a new subclass of
ActiveRecord::FixtureSet.context_class each time a fixture is rendered.
Previously, the `has_one` macro incorrectly accepts the `counter_cache` option
due to a bug, although that options was never supported nor functional on
`has_one` and `has_one ... through` relationships. It now correctly raises an
`ArgumentError` when passed that option.
For reference, this bug was introduced in 52f8e4b9.
Extract **notable changes**, **deprecations** and **removals** from
each CHANGELOG.
I tried to reference the commits and pull requests for new features
and deprecations.
In the process I also made some minor changes to the CHANGELOGS.
The 4_1_release_notes guide is declared WIP.
This prevents the following error when a MySQL index on a foreign key
column is renamed:
```
ActiveRecord::StatementInvalid: Mysql2::Error: Cannot drop index 'index_engines_on_car_id': needed in a foreign key constraint: DROP INDEX `index_engines_on_car_id` ON `engines`
```
refs: #13038.
Fixes#12812
Raise `ActiveRecord::RecordNotDestroyed` when a child marked with
`dependent: destroy` can't be destroyed.
The following code:
```ruby
class Post < ActiveRecord::Base
has_many :comments, dependent: :destroy
end
class Comment < ActiveRecord::Base
before_destroy do
return false
end
end
post = Post.create!(comments: [Comment.create!])
post.comments = [Comment.create!]
````
would result in a `post` with two `comments`.
With this commit, the same code would raise a `RecordNotDestroyed`
exception, keeping the `post` with the same `comment`.
I'm pretty confused about the addition of this method. The documentation
says that it was intended to allow the removal of values from the
default scope (in contrast to #except). However it behaves exactly the
same as except: https://gist.github.com/jonleighton/7537008 (other than
having a slightly enhanced syntax).
The removal of the default scope is allowed by
94924dc32baf78f13e289172534c2e71c9c8cade, which was not a change we
could make until 4.1 due to the need to deprecate things. However after
that change #unscope still gives us nothing that #except doesn't already
give us.
However there *is* a desire to be able to unscope stuff in a way that
persists across merges, which would allow associations to be defined
which unscope stuff from the default scope of the associated model. E.g.
has_many :comments, -> { unscope where: :trashed }
So that's what this change implements. I've also corrected the
documentation. I removed the guide references to #except as I think
unscope really supercedes #except now.
While we're here, there's also a potential desire to be able to write
this:
has_many :comments, -> { unscoped }
However, it doesn't make sense and would not be straightforward to
implement. While with #unscope we're specifying exactly what we want to
be removed from the relation, with "unscoped" we're just saying that we
want it to not have some things which were added earlier on by the
default scope. However in the case of an association, we surely don't
want *all* conditions to be removed, otherwise the above would just
become "SELECT * FROM comments" with no foreign key constraint.
To make the above work, we'd have to somehow tag the relation values
which get added when evaluating the default scope in order to
differentiate them from other relation values. Which is way too much
complexity and therefore not worth it when most use cases can be
satisfied with unscope.
Closes#10643, #11061.
This fixes a bug when merging relations of different classes.
```
Given:
Post.joins(:author).merge(Author.order(name: :desc)).to_sql
Before:
SELECT "posts".* FROM "posts"
INNER JOIN "authors" ON "authors"."id" = "posts"."author_id"
ORDER BY "posts"."name" DESC
After:
SELECT "posts".* FROM "posts"
INNER JOIN "authors" ON "authors"."id" = "posts"."author_id"
ORDER BY "authors"."name" DESC
```
* A non-zero exit status allows subsequent shell commands to be chained
together such as: `rake db:reset test:prepare && rspec && cap deploy`
(if you're feeling brave :)
* Any exceptions raised during the `create` and `drop` tasks are caught
in order to print a "pretty" message to the user. Unfortunately doing
so prevents rake from aborting with a non-zero exit status to the shell.
* Therefore we re-raise the exceptions after the "pretty" message and
re-catch them in the task.
* From the task we explicitly exit with a non-zero status. This method
was chosen (rather than just letting rake fail from the exception) so
that the backtrace is suppressed and the output to stderr is
unchanged.
* Update activerecord CHANGELOG
The log output used to be confusing in situation where type casting has
"unexpected" effects. For example when finding records with a `String`.
BEFORE:
irb(main):002:0> Event.find("im-no-integer")
D, [2013-11-09T11:10:28.998857 #1706] DEBUG -- : Event Load (4.5ms) SELECT "events".* FROM "events" WHERE "events"."id" = $1 LIMIT 1 [["id", "im-no-integer"]]
AFTER:
irb(main):002:0> Event.find("im-no-integer")
D, [2013-11-09T11:10:28.998857 #1706] DEBUG -- : Event Load (4.5ms) SELECT "events".* FROM "events" WHERE "events"."id" = $1 LIMIT 1 [["id", 0]]
