ANN: Sequel 3.46.0 Released

Ruby
1

Sequel is a lightweight database access toolkit for Ruby.

  • Sequel provides thread safety, connection pooling and a concise
    DSL for constructing SQL queries and table schemas.
  • Sequel includes a comprehensive ORM layer for mapping records to
    Ruby objects and handling associated records.
  • Sequel supports advanced database features such as prepared
    statements, bound variables, stored procedures, savepoints,
    two-phase commit, transaction isolation, master/slave
    configurations, and database sharding.
  • Sequel currently has adapters for ADO, Amalgalite, CUBRID,
    DataObjects, DB2, DBI, Firebird, IBM_DB, Informix, JDBC, MySQL,
    Mysql2, ODBC, OpenBase, Oracle, PostgreSQL, SQLite3, Swift, and
    TinyTDS.

Sequel 3.46.0 has been released and should be available on the gem
mirrors.

= New Features

  • Dataset#first! has been added. This is identical to #first,
    except where #first would return nil due to no row matching,
    #first! raises a Sequel::NoMatchingRow exception. The main
    benefit here is that a standard exception class is now used,
    so external libraries can deal with these exceptions appropriately
    (such as web applications returning a 404 error).

  • Dataset#with_pk! has been added to model datasets. Similar to
    #first!, this raises a Sequel::NoMatchingRow exception instead of
    returning nil if there is no matching row.

  • A drop_foreign_key method has been added to the alter_table
    generator:

    alter_table(:tab){drop_foreign_key :col}

    This relies on foreign_key_list working and including the name
    of the foreign key. Previously, you’d have to drop the foreign key
    constraint before dropping the column in some cases.

  • Column constraints can now be named using :*_constraint_name
    options:

    create_table(:tab) do
    primary_key :id, :primary_key_constraint_name=>:pk_name
    foriegn_key :t_id, :t, :foreign_key_constraint_name=>:fk_name,
    :unique=>true, :unique_constraint_name=>:uk_name
    end

    This makes it easier to name constraints, which has always been
    recommended as it makes it easier to drop such constraints in the
    future.

  • On Microsoft SQL Server, Dataset#cross_apply and #outer_apply have
    been added to use CROSS/OUTER APPLY. These are useful if you
    want to join a table to the output of a function that takes the
    table as an argument.

= Other Improvements

  • The connection pools are now faster when using the
    :connection_handling=>:queue option.

  • External connection pool classes can now be loaded automatically by
    the :pool_class option.

  • Database#each_server now raises if not given a block. Previously,
    it just leaked Database references.

  • On Microsoft SQL Server, ] characters are now escaped correctly in
    identifiers.

  • On PostgreSQL, infinite dates are also handled when using
    Database#convert_infinite_timestamps. Previously, infinite dates
    were incorrectly converted to 0000-01-01.

  • The associations, composition, serialization, and dirty plugins
    now clear caches stored in the instance in some additional cases,
    such as when saving model instances when the dataset supports
    insert_select.

  • Model#validates_type in the validation_helpers plugin now handles
    false values correctly.

  • The string_stripper plugin has been fixed to not change the result
    of Model.set_dataset.

  • You can now drop primary key constraints on H2, using:

    alter_table(:tab){drop_constraint :foo, :type=>:primary_key}

  • The jdbc/as400 adapter has been fixed, it was broken starting in
    Sequel 3.44.0.

  • A Security guide has been added explaining various security issues
    to think about when using Sequel.

= Backwards Compatibility

  • The change to make associations, composition, serialization, and
    dirty now clear caches after saving when the dataset supports
    insert_select can break code that expected the previous behavior.
    For example:

    artist = Artist[1]
    artist.has_albums # => false

    album = Album.new(:artist=>artist)
    def album.after_create
    super
    artist.update(:has_albums=>true)
    end
    album.save

    artist.has_albums # => false

    Such code should either refresh the artist after saving the album,
    or use album.artist.has_albums. You already had to do that if
    the dataset did not support insert_select; the impetus for this
    change was to make the behavior consistent.

  • Decimal/numeric columns are now strictly typecast by default,
    similar to integer and real/double precision columns. If you want
    the previous loose typecasting to for decimal/numeric columns,
    use the looser_typecasting extension.

  • External adapters that called Database.set_adapter_scheme with a
    string should change to using a symbol.

  • Dataset#select_map, #select_order_map, and #get now raise an
    exception if they are passed a plain string inside an array.
    If you do want to use a plain string, you now need to alias it:

    dataset.get([Sequel.as(‘string’, :some_alias)])

= Sequel 4 Implementation Planning

Thanks,
Jeremy