master (unreleased)

0.25.0 (2025-02-03)

Track start/finish time of background data migrations

Note: Make sure to run bin/rails generate online_migrations:upgrade if using background migrations.
Add new state for errored background migrations
- errored - migration raised an error during last run
- failed - migration raises an error when running and retry attempts exceeded
Fix thread safety issue for lock retrier

Note: Lock retrier changed its API (LockRetrier#connection accessor was removed and LockRetrier#with_lock_retries now accepts a connection argument). This change might be of interest if you implemented a custom lock retrier class.

0.24.0 (2025-01-20)

Add ability to run a separate background migrations scheduler per shard
Revert "Prevent multiple instances of schedulers from being running simultaneously"

The feature was implemented using advisory locks, but they do not always play nicely with the database poolers, so the feature was reverted. It is expected now for user's code to prevent multiple instances of the schedulers from being run (by wrapping it into Redis lock etc).

0.23.0 (2025-01-13)

Prevent multiple instances of schedulers from being running simultaneously
Reduce default batch sizes for background data migrations

batch_size was 20_000, now 1_000; sub_batch_size was 1_000, now 100
Remove deprecated code
Drop support for PostgreSQL < 12
Drop support for Ruby < 3.0 and Rails < 7.0

0.22.0 (2025-01-03)

Make background data migrations scheduler run a single migration at a time

This is similar to background schema migrations scheduler's behavior. Running multiple migrations at a time can cause unneeded database load and other bad effects.
Add #pausable?, #can_be_cancelled? and #can_be_paused? helpers to background migrations

0.21.0 (2024-12-09)

Fix add_foreign_key when referencing same table via different columns
Make validate_not_null_constraint, remove_foreign_key and remove_check_constraint idempotent

Add helpers for validating constraints in background

validate_foreign_key_in_background(:users, :companies)
validate_constraint_in_background(:users, "first_name_not_null")

0.20.2 (2024-11-11)

Fix running background migrations over relations with duplicate records

0.20.1 (2024-11-05)

Fix background data migrations to work with includes/eager_load on relation
Fix problem with running migrations for activerecord 8.0.0.rc2

0.20.0 (2024-10-21)

Enhance columns removal check to check indexes where and include options
Do not wait before running retried background migrations

0.19.6 (2024-09-26)

Fix add_reference_concurrently when adding non polymorphic references
Fix progress for background migrations with small number of records

0.19.5 (2024-09-20)

Fix add_reference_concurrently when adding polymorphic references

0.19.4 (2024-09-02)

Fix an edge case for background schema migrations

If you use background schema migrations, you need to run
```
bin/rails generate online_migrations:upgrade
bin/rails db:migrate
```
Fix retrying running stuck background schema migrations
Fix renaming columns for tables with long names

0.19.3 (2024-08-09)

Fix idempotency for add_index/remove_index for expression indexes

0.19.2 (2024-07-09)

Fix add_reference_concurrently to be idempotent when adding a foreign key
Fix enqueue_background_data_migration to be idempotent

0.19.1 (2024-05-24)

Fix add_index_in_background to be idempotent

0.19.0 (2024-05-21)

Add ability to cancel background migrations

0.18.0 (2024-05-07)

Fix setting started_at/finished_at for parents of sharded background schema migrations
Improve retrying of failed sharded background migrations
Fix a bug when retried background data migration can not start
Do not run multiple background schema migrations on the same table at the same time

0.17.1 (2024-04-28)

Fix raising in development when using sharding and background index creation/removal was not enqueued

0.17.0 (2024-04-23)

Fix background migrations #progress possibility to fail with zero division error
Add ensure_background_data_migration_succeeded and ensure_background_schema_migration_succeeded migration helpers
Raise in development when background index creation/removal was not enqueued
Suggest two migrations for adding foreign keys
Reraise errors when running background schema migrations inline

0.16.1 (2024-03-29)

Improve error message when background schema migration name is already taken
Fix copying column background migration to work with primary keys added via initialize_column_type_change

0.16.0 (2024-03-28)

Add support for asynchronous creation/removal of indexes

See docs/background_schema_migrations.md for the feature description.

0.15.0 (2024-03-19)

Reraise errors when running background migrations inline
Add remove_background_migration migration helper
Allow adding bigint foreign keys referencing integer primary keys
Fix add_reference_concurrently to check for mismatched key types

0.14.1 (2024-02-21)

Fix MigrationRunner to consider run_background_migrations_inline proc

0.14.0 (2024-02-01)

Add ability to configure whether background migrations should be run inline

The previous behavior of running inline in development and test environments is preserved, unless overriden.
```
config.run_background_migrations_inline = -> { Rails.env.local? }
```

0.13.1 (2024-01-23)

Fix calculation of batch ranges for background migration created with explicit ranges

0.13.0 (2024-01-22)

Add ability to configure the path where generated background migrations will be placed

# It is placed in lib/ by default.
config.background_migrations.migrations_path = "app/lib"

Reduce number of queries needed to calculate batch ranges for background migrations
Fix finalize_column_type_change to not recreate already existing indexes on the temporary column
Remove potentially heavy queries used to get the ranges of a background migration

0.12.0 (2024-01-18)

Require passing model name for background migration helpers when using multiple databases
Add statement_timeout configuration option
Make lock_timeout argument optional for config.lock_retrier

This way, a default lock timeout value will be used (configured in database.yml or for the database user).
Fix a bug that can lead to unfinished children of a sharded background migration

0.11.1 (2024-01-11)

Fix calculation of batch ranges for sharded background migrations

0.11.0 (2024-01-09)

Support sharding for background migrations

Now, if a relation inside background migration definition is defined on a sharded model, then that background migration would automatically run on all the shards.

To get all the new sharding related schema changes, you need to run:
```
$ bin/rails generate online_migrations:upgrade
$ bin/rails db:migrate
```
Change background migration progress to return values in range from 0.0 to 100.0

Previously, these were values in range from 0.0 to 1.0 and caused confusion
Copy exclusion constraints when changing column type
Update revert_finalize_columns_type_change to not remove indexes, foreign keys etc
Fix verbose query logging when ActiveRecord::Base.logger is nil

Add a shortcut for running background migrations

# Before:
OnlineMigrations::BackgroundMigrations::Scheduler.run
# After
OnlineMigrations.run_background_migrations

Add support for :type_cast_function to initialize_column_type_change helper
Drop support for Ruby < 2.7 and Rails < 6.1

0.10.0 (2023-12-12)

Add auto_analyze configuration option
Add alphabetize_schema configuration option
Fix backfill_column_for_type_change_in_background for cast expressions
Fix copying indexes with long names when changing column type
Enhance error messages with the link to the detailed description

0.9.2 (2023-11-02)

Fix checking which expression indexes to copy when changing column type

0.9.1 (2023-10-30)

Fix copying expression indexes when changing column type

0.9.0 (2023-10-27)

Add ability to use custom raw sql for backfill_column_for_type_change's type_cast_function

backfill_column_for_type_change(:users, :company_id, type_cast_function: Arel.sql("company_id::integer"))

Fix version safety with revert

0.8.2 (2023-09-26)

Promote check constraint to NOT NULL on PostgreSQL >= 12 when changing column type
Fix safety_assured with revert

0.8.1 (2023-08-04)

Fix update_columns_in_batches when multiple columns are passed
Fix reverting adding/removing not null and text limit constraints

0.8.0 (2023-07-24)

Add check for change_column_default
Add check for add_unique_constraint (Active Record >= 7.1)
Add check for add_column with stored generated columns

0.7.3 (2023-05-30)

Fix removing columns having expression indexes on them

0.7.2 (2023-03-08)

Suggest additional steps for safely renaming a column if Active Record enumerate_columns_in_select_statements setting is enabled (implemented in Active Record 7+, disabled by default)
Fix add_reference_concurrently to correctly check for existence of foreign keys
Fix column quoting in add_not_null_constraint

0.7.1 (2023-02-22)

Fix Schema Cache to correctly retrieve metadata from renamed tables

0.7.0 (2023-02-14)

Add support for renaming multiple columns at once in the same table
Fix quoting table/column names across the library
Fix deffered foreign keys support in add_foreign_key (Active Record >= 7)
Reset attempts of failing jobs before executing background migration inline

0.6.0 (2023-02-04)

Ignore internal Active Record migrations compatibility related options when suggesting a safe column type change
Added check for add_exclusion_constraint
Fix preserving old column options (:comment and :collation) when changing column type
Set NOT NULL during new column creation when changing column type for PostgreSQL >= 11

0.5.4 (2023-01-03)

Support ruby 3.2.0

0.5.3 (2022-11-10)

Fix removing index by name
Fix multiple databases support for start_after and target_version configs
Fix error when Rails defined without Rails.env
Improve error message for adding column with a NULL default for PostgreSQL < 11

0.5.2 (2022-10-04)

Fix sequence resetting in tests that use fixtures

Fix update_column_in_batches for SQL subquery values

It generated inefficient queries before, e.g.:

update_column_in_batches(:users, :comments_count, Arel.sql(<<~SQL))
  (select count(*) from comments where comments.user_id = users.id)
SQL

Generated SQL queries before:

update users
set comments_count = (..count subquery..)
where comments_count is null or comments_count != (..count subquery..)

Generated SQL queries now:

update users set comments_count = (..count subquery..)

Fix check for add_column with default: nil for PostgreSQL < 11
Replacing a unique index when other unique index with the prefix of columns exists is safe

0.5.1 (2022-07-19)

Raise for possible index corruption in all environments (previously, the check was made only in the production environment)

0.5.0 (2022-06-23)

Added check for index corruption with PostgreSQL 14.0 to 14.3
No need to separately remove indexes when removing a column from the small table

Add ability to perform specific action on a relation or individual records using background migrations

Example, assuming you have lots and lots of fraud likes:

class DeleteFraudLikes < ActiveRecord::Migration[7.0]
  def up
    perform_action_on_relation_in_background("Like", { fraud: true }, :delete_all)
  end
end

Example, assuming you added a new column to the users and want to populate it:

class User < ApplicationRecord
  def generate_invite_token
    self.invite_token = # some complex logic
  end
end

perform_action_on_relation_in_background("User", { invite_token: nil }, :generate_invite_token)

You can use delete_all/destroy_all/update_all for the whole relation or run specific methods on individual records.

Add ability to delete records associated with a parent object using background migrations

  class Link < ActiveRecord::Base
    has_many :clicks
  end

  class Click < ActiveRecord::Base
    belongs_to :link
  end

  class DeleteSomeLinkClicks < ActiveRecord::Migration[7.0]
    def up
      some_link = ...
      delete_associated_records_in_background("Link", some_link.id, :clicks)
    end
  end

Add ability to delete orphaned records using background migrations

  class User < ApplicationRecord
    has_many :posts
  end

  class Post < ApplicationRecord
    belongs_to :author, class_name: 'User'
  end

  class DeleteOrphanedPosts < ActiveRecord::Migration[7.0]
    def up
      delete_orphaned_records_in_background("Post", :author)
    end
  end

0.4.1 (2022-03-21)

Fix missing options in suggested command for columns removal
Fix retrieving raw postgresql connection

0.4.0 (2022-03-17)

Lazy load this gem

Add ability to reset counter caches using background migrations

  class User < ApplicationRecord
    has_many :projects
  end

  class Project < ApplicationRecord
    belongs_to :user, counter_cache: true
  end

  class ResetUsersProjectsCount < ActiveRecord::Migration[7.0]
    def up
      reset_counters_in_background("User", :projects)
    end
  end

Accept 0 as batch_pause value for background migrations
Ignore default scopes in CopyColumn and BackfillColumn background migrations
Raise an error for unsupported database versions
Fix backfilling code in suggestion for changing column's NOT NULL

New safe operations

Changing between text and citext when not indexed
Changing a string column to a citext column when not indexed
Changing a citext column to a string column with no length limit
Increasing the :precision of an interval column
Changing a cidr column to an inet column
Changing an xml column to a text column
Changing an xml column to a string column with no :limit
Changing a bit column to a bit_varying column
Increasing or removing the :limit of a bit_varying column

New unsafe operations

Decreasing :precision of a datetime column
Decreasing :limit of a timestamptz column
Decreasing :limit of a bit_varying column
Adding a :limit to a bit_varying column

0.3.0 (2022-02-10)

Support ActiveRecord 7.0+ versioned schemas
Check for addition of single table inheritance column

See Adding a single table inheritance column for details
Add a way to log every SQL query to stdout

See Verbose SQL logs for details
Ignore new tables when checking for removing table with multiple fkeys
Fix backfilling column in add_column_with_default when default is an expression

0.2.0 (2022-01-31)

Check removing a table with multiple foreign keys

Check for mismatched reference column types

For example, it detects cases like:

class AddUserIdToProjects < ActiveRecord::Migration[7.0]
  def change
    add_column :projects, :user_id, :integer
  end
end

where users.id is of type bigint.

Add support for multiple databases to start_after and target_version configuration options

OnlineMigrations.configure do |config|
  config.start_after = { primary: 20211112000000, animals: 20220101000000 }
  config.target_version = { primary: 10, animals: 14.1 }
end

Do not suggest ignored_columns when removing columns for Active Record 4.2 (ignored_columns was introduced in 5.0)
Check replacing indexes

For example, you have an index on projects.creator_id. But decide, it is better to have a multicolumn index on [creator_id, created_at]:
```
class AddIndexOnCreationToProjects < ActiveRecord::Migration[7.0]
  disable_ddl_transaction!

  def change
    remove_index :projects, :creator_id, algorithm: :concurrently # (1)
    add_index :projects, [:creator_id, :created_at], algorithm: :concurrently # (2)
  end
end
```
If there is no existing indexes covering creator_id, removing an old index (1) before replacing it with the new one (2) might result in slow queries while building the new index. A safer approach is to swap removing the old and creation of the new index operations.

0.1.0 (2022-01-17)

First release

Files

CHANGELOG.md

Latest commit

History