= New Features

* Sequel now has vastly improved support for Microsoft Access.

* Sequel now supports the CUBRID database, with a cubrid adapter
  that uses the cubrid gem, and a jdbc/cubrid adapter for accessing
  CUBRID via JDBC on JRuby.

* The association_pks plugin now supports composite keys.

* Database#transaction now accepts a :disconnect=>:retry option,
  in which case it will automatically retry the block if it
  detects a disconnection.  This is potentially dangerous, and
  should only be used if the entire block is idempotent.  There
  is also no checking against an infinite retry loop.

* SQL::CaseExpression#with_merged_expression has been added, for
  converting a CaseExpression with an associated expression to
  one without an associated expression, by merging the expression
  into each condition.

= Other Improvements

* Sequel now quotes arguments/columns in common table expressions.

* Sequel now handles nil values correctly in the pg_row extension.

* Sequel::Postgres::HStore instances can now be marshalled.

* Sequel now uses clob for String :text=>true types on databases that
  don't support a text type.

* On PostgreSQL, Sequel now quotes channel identifier names when using
  LISTEN/NOTIFY.

* On PostgreSQL, Sequel now correctly handles the case where named
  type conversion procs have been added before the Database object is
  instantiated.

* On DB2, Sequel now explicitly sets NOT NULL for unique constraint
  columns instead of foreign key columns.  DB2 does not allow columns
  in unique constraints to be NULL, but does allow foreign key columns
  to be NULL.

* In the oracle adapter, clob values are now returned as ruby strings
  upon retrieval.

* Sequel now detects more types of disconnections in the postgres,
  mysql, and mysql2 adapters.

* If a database provides a default column value that isn't a ruby
  string, it is used directly as the ruby default, instead of causing
  the schema parsing to fail.

= Backwards Compatibility

* Code using Sequel's oracle adapter that expected clob values to be
  returned as OCI8::CLOB instances needs to be modified to work with
  ruby strings.

* Because Sequel now quotes column names in common table expressions,
  those names are now case sensitive, which could break certain poorly
  coded queries.  Similar issues exist with the quoting of channel
  identifier names in LISTEN/NOTIFY on PostgreSQL.

* The private Database#requires_return_generated_keys? method
  has been removed from the jdbc adapter.  Custom jdbc subadapters
  relying on this method should override the private
  Database#execute_statement_insert method instead to ensure that
  RETURN_GENERATED_KEYS is used for insert statements.

* The private Dataset#argument_list and #argument_list_append methods
  have been removed.