New Features¶ ↑

• Sequel.[] has been added as an alias to Sequel.expr. This makes it a little easier to get Sequel-specific objects:

  Sequel[:table].*                  # "table".*
  Sequel[:table__column].as(:alias) # "table"."column" AS "alias"
  Sequel[:column] + 1               # ("column" + 1)
  

• The timestamps plugin now supports an :allow_manual_update option. If this option is used, the timestamps plugin will not override the update timestamp when saving if the user has modified it since retrieving the object.

• The touch plugin now also touches associations on create in addition to update and delete.

• The IntegerMigrator now supports a :relative option, which will migrate that many migrations up (for positive numbers) or down (for negative numbers).

• Database#rollback_checker has been added, which returns a callable that can be called later to determine whether the transaction ended up committing or rolling back. So if you may need to check transaction status at some future point, and don’t need immediate action on rollback/commit, it is better to use a rollback checker than to add an after commit/rollback hook.

  rbc = nil
  DB.transaction do
    rbc = DB.rollback_checker
    rbc.call #=> nil
  end
  rbc.call # => false
  
  DB.transaction(:rollback=>:always) do
    rbc = DB.rollback_checker
  end
  rbc.call # => true
  

• The add_column schema method now supports an :if_not_exists option on PostgreSQL 9.6+, which will only add the column if it does not already exist:

  DB.add_column :t, :c, Integer, :if_not_exists=>true
  # ALTER TABLE "t" ADD COLUMN IF NOT EXISTS "c" integer
  

• The add_column schema method now supports an :after and :first option on MySQL to add the column after an existing column or as the first column:

  DB.add_column :t, :c, Integer, :first=>true
  # ALTER TABLE `t` ADD COLUMN `c` integer FIRST
  DB.add_column :t, :c1, Integer, :after=>:c2
  # ALTER TABLE `t` ADD COLUMN `c1` integer AFTER `c2`
  

• JSONBOp#insert has been added to the pg_json_ops extension, which supports the new jsonb_insert function added in PostgreSQL 9.6+:

  Sequel.pg_jsonb_op(:c).insert(%w'0 a', 'a'=>1)
  # jsonb_insert("c", ARRAY['0','a'], '{"a":1}'::jsonb, false)
  

• Dataset#full_text_search on PostgreSQL now supports a :to_tsquery=>:phrase option, to enable the native phrase searching added in PostgreSQL 9.6+:

  DB[:t].full_text_search(:c, 'foo bar', :to_tsquery=>:phrase)
  # SELECT * FROM "t"
  # WHERE
  #   (to_tsvector(CAST('simple' AS regconfig), (COALESCE("c", '')))
  #   @@ phraseto_tsquery(CAST('simple' AS regconfig), 'foo bar'))
  

• Sequel::Database.set_shared_adapter_scheme has been added, allowing external adapters to add support for Sequel’s mock adapter. External adapters should have a shared adapter requirable at sequel/adapters/shared/adapter_name, that uses the following format:

  # in sequel/adapters/shared/mydb
  module Sequel::MyDB
    Sequel::Database.set_shared_adapter_scheme :mydb, self
  
    def self.mock_adapter_setup(db)
      # Any mock-adapter specific setup to perform on the
      # given Database instance
    end
  
    module DatabaseMethods
      # methods for all Database objects using this adapter
    end
  
    module DatasetMethods
      # methods for all Dataset objects using this adapter
    end
  end
  

Other Improvements¶ ↑

• The hook_class_methods plugin only adds a Database transaction hook if one of the after commit/rollback hook class methods is actually used. This means that loading the plugin no longer keeps all saved/deleted objects in memory until transaction commit.

• The active_model plugin now uses a rollback checker instead of an after_rollback hook, so models that use the active_model plugin no longer store all saved model instances in memory until transaction commit.

• When using the IntegerMigrator, attempting to migrate to a migration number above the maximum will now migrate to the lastest version, and attempting to migrate to a migration number below 0 will now migrate all the way down.

• The pg_interval extension now supports ActiveSupport::Duration objects that use week and hour parts (new in ActiveSupport 5).

Backwards Compatibility¶ ↑

• The change to the touch plugin to touch associations on create could possibly affect existing behavior, so if you are using this plugin, you should test that this does not cause any problems.

• External adapters that tried to add support for the mock adapter now need to update their code to use the new Sequel::Database.set_shared_adapter_scheme method.