rails/activerecord/CHANGELOG.md

• Fix an Active Record DateTime field NoMethodError caused by incomplete datetime. Bug #24195

  Sen Zhang

• Allow slice to take an array of methods (without need for splatting).

  Cohen Carlisle

• Improved partial writes with HABTM and has many through associations to fire database query only if relation has been changed.

  Fixes #19663.

  Mehmet Emin İNAÇ

• Deprecate passing arguments and block at the same time to ActiveRecord::QueryMethods#select.

  Prathamesh Sonpatki

• Optimistic locking: Added ability update locking_column value. Ignore optimistic locking if update with new locking_column value.

  bogdanvlviv

• Fixed: Optimistic locking does not work well with null in the database.

  Fixes #26024

  bogdanvlviv

• Fixed support for case insensitive comparisons of text columns in PostgreSQL.

  Edho Arief

• Serialize JSON attribute value nil as SQL NULL, not JSON null

  Trung Duc Tran

• Return true from update_attribute when the value of the attribute to be updated is unchanged.

  Fixes #26593.

  Prathamesh Sonpatki

• Always store errors details information with symbols.

  When the association is autosaved we were storing the details with string keys. This was creating inconsistency with other details that are added using the Errors#add method. It was also inconsistent with the Errors#messages storage.

  To fix this inconsistency we are always storing with symbols. This will cause a small breaking change because in those cases the details could be accessed as strings keys but now it can not.

  Fix #26499.

  Rafael Mendonça França, Marcus Vieira

• Calling touch on a model using optimistic locking will now leave the model in a non-dirty state with no attribute changes.

  Fixes #26496.

  Jakob Skjerning

• Using a mysql2 connection after it fails to reconnect will now have an error message saying the connection is closed rather than an undefined method error message.

  Dylan Thacker-Smith

• PostgreSQL array columns will now respect the encoding of strings contained in the array.

  Fixes #26326.

  Sean Griffin

• Inverse association instances will now be set before after_find or after_initialize callbacks are run.

  Fixes #26320.

  Sean Griffin

• Remove unnecessarily association load when a belongs_to association has already been loaded then the foreign key is changed directly and the record saved.

  James Coleman

• Remove standardized column types/arguments spaces in schema dump.

  Tim Petricola

• Avoid loading records from database when they are already loaded using the pluck method on a collection.

  Fixes #25921.

  Ryuta Kamizono

• Remove text default treated as an empty string in non-strict mode for consistency with other types.

  Strict mode controls how MySQL handles invalid or missing values in data-change statements such as INSERT or UPDATE. If strict mode is not in effect, MySQL inserts adjusted values for invalid or missing values and produces warnings.

  def test_mysql_not_null_defaults_non_strict
    using_strict(false) do
      with_mysql_not_null_table do |klass|
        record = klass.new
        assert_nil record.non_null_integer
        assert_nil record.non_null_string
        assert_nil record.non_null_text
        assert_nil record.non_null_blob
  
        record.save!
        record.reload
  
        assert_equal 0,  record.non_null_integer
        assert_equal "", record.non_null_string
        assert_equal "", record.non_null_text
        assert_equal "", record.non_null_blob
      end
    end
  end
  

  https://dev.mysql.com/doc/refman/5.7/en/sql-mode.html#sql-mode-strict

  Ryuta Kamizono

• Sqlite3 migrations to add a column to an existing table can now be successfully rolled back when the column was given and invalid column type.

  Fixes #26087

  Travis O'Neill

• Deprecate sanitize_conditions. Use sanitize_sql instead.

  Ryuta Kamizono

• Doing count on relations that contain LEFT OUTER JOIN Arel node no longer force a DISTINCT. This solves issues when using count after a left_joins.

  Maxime Handfield Lapointe

• RecordNotFound raised by association.find exposes id, primary_key and model methods to be consistent with RecordNotFound raised by Record.find.

  Michel Pigassou

• Hashes can once again be passed to setters of composed_of, if all of the mapping methods are methods implemented on Hash.

  Fixes #25978.

  Sean Griffin

• Fix the SELECT statement in #table_comment for MySQL.

  Takeshi Akima

• Virtual attributes will no longer raise when read on models loaded from the database

  Sean Griffin

• Support calling the method merge in scope's lambda.

  Yasuhiro Sugino

• Fixes multi-parameter attributes conversion with invalid params.

  Hiroyuki Ishii

• Add newline between each migration in structure.sql.

  Keeps schema migration inserts as a single commit, but allows for easier git diffing.

  Fixes #25504.

  Grey Baker, Norberto Lopes

• The flag error_on_ignored_order_or_limit has been deprecated in favor of the current error_on_ignored_order.

  Xavier Noria

• Batch processing methods support limit:

  Post.limit(10_000).find_each do |post|
    # ...
  end
  

  It also works in find_in_batches and in_batches.

  Xavier Noria

• Using group with an attribute that has a custom type will properly cast the hash keys after calling a calculation method like count.

  Fixes #25595.

  Sean Griffin

• Fix the generated #to_param method to use omission: '' so that the resulting output is actually up to 20 characters, not effectively 17 to leave room for the default "...". Also call #parameterize before #truncate and make the separator: /-/ to maximize the information included in the output.

  Fixes #23635.

  Rob Biedenharn

• Ensure concurrent invocations of the connection reaper cannot allocate the same connection to two threads.

  Fixes #25585.

  Matthew Draper

• Inspecting an object with an associated array of over 10 elements no longer truncates the array, preventing inspect from looping infinitely in some cases.

  Kevin McPhillips

• Removed the unused methods ActiveRecord::Base.connection_id and ActiveRecord::Base.connection_id=.

  Sean Griffin

• Ensure hashes can be assigned to attributes created using composed_of.

  Fixes #25210.

  Sean Griffin

• Fix logging edge case where if an attribute was of the binary type and was provided as a Hash.

  Jon Moss

• Handle JSON deserialization correctly if the column default from database adapter returns '' instead of nil.

  Johannes Opper

• Introduce ActiveRecord::TransactionSerializationError for catching transaction serialization failures or deadlocks.

  Erol Fornoles

• PostgreSQL: Fix db:structure:load silent failure on SQL error.

  The command line flag -v ON_ERROR_STOP=1 should be used when invoking psql to make sure errors are not suppressed.

  Example:

  psql -v ON_ERROR_STOP=1 -q -f awesome-file.sql my-app-db
  

  Fixes #23818.

  Ralin Chimev

Please check 5-0-stable for previous changes.