New Features¶ ↑

• Dataset#with_* methods have been added as equivalents for a few Dataset#*= methods, but instead of modifying the receiver, they return a modified copy, similar to the dataset query methods. Specific methods added:

  with_extend	Extends clone with given modules
  with_row_proc	Modifies row_proc in clone
  with_quote_identifiers	Modifies quote_identifiers setting in clone
  with_identifier_input_method	Modifies identifier_input_method setting in clone
  with_identifier_output_method	Modifies identifier_output_method setting in clone

  Similarly, on Microsoft SQL Server, a with_mssql_unicode_strings method has been added, which returns a clone with the mssql_unicode_strings setting modified.

• On DB2, Sequel now supports an :offset_strategy Database option, which can be set to :limit_offset for “LIMIT X OFFSET Y” or :offset_fetch for “OFFSET Y FETCH FIRST X ROWS ONLY”. Depending on what version of DB2 is used and how DB2 is configured, it’s possible one of these strategies will work. For backwards compatibility, the current default is still to emulate offsets using the ROW_NUMBER window function.

• In the json_serializer plugin, you can now use an Sequel::SQL::AliasedExpression instance as an association name value, which allows you to rename the association in the resulting JSON:

  album.to_json(:include=>{Sequel.as(:album, :s)=>{:only=>:name}})
  # => '{"id":1,"name":"RF","artist_id":2,"s":{"name":"YJM"}}'
  

Other Improvements¶ ↑

• The association dataset methods now correctly handle cases where one of the keys is nil. Previously, they would incorrectly use an IS NULL predicate in such cases. Now, they use a false predicate.

• The hook_class_methods plugin handling of commit hooks has been fixed. The implementation of commit hooks (but not rollback hooks) was broken in hook_class_methods starting in 4.39.0 due to changes to avoid keeping references to all model instances until the transaction was committed or rolled back.

• Using the Fixnum schema method no longer raises a warning on ruby 2.4+, as it now uses the Integer class instead of the Fixnum constant.

• The ado adapter has been greatly improved. It now avoids memory leaks, has much better type handling, and passes almost all specs. Note that the ado adapter’s behavior can change depending on the version of ruby in use, try to use ruby 2.2+ for best compatibility.

• Dataset#graph no longer mutates the receiver. Previously, it set an empty hash as the :graph option in the receiver, which was unintentional and not desired.

• Pure java exceptions that don’t support the message= method are now handled properly when reraising the exception on connection errors in the jdbc adapter.

Backwards Compatibility¶ ↑

• Support for using the Bignum constant as a generic type has been removed, as was preannounced in the 4.36.0 release notes. Users should switch to using the :Bignum constant if they haven’t already.

• Users of the ado adapter may need to update their code now that the ado adapter correctly handles most types.

• The spec_*_w rake tasks in the repository now require ruby 2.4+ and use the warning library for filtering warnings, instead of trying to filter warnings with egrep.