# ANN: Sequel 3.2.0 Released **URL:** \ **Category:** Ruby\ **Created:** [July 2, 2009, 6:29pm UTC](https://www.ruby-forum.com/t/ann-sequel-3-2-0-released/171452 "2009-07-02T18:29:34Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![nerdmaster](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/n/c68b51/32.png) [@nerdmaster](https://www.ruby-forum.com/u/nerdmaster)\ **Post date:** [July 2, 2009, 6:29pm UTC](https://www.ruby-forum.com/t/ann-sequel-3-2-0-released/171452/1 "2009-07-02T18:29:34Z")
Sequel is a lightweight database access toolkit for Ruby. - Sequel provides thread safety, connection pooling and a concise DSL for constructing database queries and table schemas. - Sequel also includes a lightweight but 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, master/slave configurations, and database sharding. - Sequel makes it easy to deal with multiple records without having to break your teeth on SQL. - Sequel currently has adapters for ADO, Amalgalite, DataObjects, DB2, DBI, Firebird, Informix, JDBC, MySQL, ODBC, OpenBase, Oracle, PostgreSQL and SQLite3. Sequel 3.2.0 has been released and should be available on the gem mirrors. The 3.2.0 release adds numerous improvements: ## New Features - Common table expressions (CTEs) are now supported. CTEs use the SQL WITH clause, and specify inline views that queries can use. They also support a recursive mode, where the CTE can recursively query its own output, allowing you do do things like load all branches for a given node in a plain tree structure. - SQL window functions are now supported, and a DSL has been added to ease their creation. Window functions act similarly to aggregate functions but operate on sliding ranges of rows. - Schema information for columns now includes a :ruby\_default entry which contains a ruby object that represents the default given by the database (which is stored in :default). Not all :default entries can be parsed into a :ruby\_default, but if the schema\_dumper extension previously supported it, it should work. - Methods to create compound datasets (union, intersect, except), now take an options hash instead of a true/false flag. The previous API is still supported, but switching to specifying the ALL setting using :all=\>true is recommended. - Dataset#ungraphed was added that removes the graphing information from the dataset. This allows you to use Dataset#graph for the automatic aliasing, or #eager\_graph for the automatic aliasing and joining, and then remove the graphing information so that the resulting objects will not be split into subhashes or associations. - There were some introspection methods added to Dataset to describe which capabilities that dataset does or does not support: - Dataset#qualify was added, which is like qualify\_to with a default of first\_source. - You can now specify the table and column Sequel::Migrator will use to record the current schema version. The new Migrator.run method must be used to use these new options. - The JDBC adapter now accepts :user and :password options, instead of requiring them to be specified in the connection string and handled by the JDBC driver. This should allow connections to Oracle using the Thin JDBC driver. - You can now specify the max\_connections, pool\_timeout, and single\_threaded settings directly in the connection string: - Dataset#on\_duplicate\_key\_update now affects Dataset#insert when using MySQL. - You can now specify the :opclass option when creating PostgreSQL indexes. Currently, this only supports a single operator class for all columns. If you need different operator classes per column, please post on sequel-talk. - Model#autoincrementing\_primary\_key was added and can be used if the autoincrementing key isn’t the same as the primary key. The only likely use for this is on MySQL MyISAM tables with composite primary keys where only one of the composite parts is autoincrementing. - You can now use database column values as search patterns and specify the text to search as a String or Regexp: - The Dataset#dataset\_alias private method was added. It can be overridden if you have tables named t0, t1, etc and want to make sure the default dataset aliases that Sequel uses do not clash with existing table names. - Sequel now raises an Error if you call Sequel.connect with something that is not a Hash or String. - bin/sequel now accepts a -N option to not test the database connection. - An opening\_databases.rdoc file was added to the documentation directory, which should be a good introduction for new users about how to set up your Database connection. ## Other Improvements - MySQL native adapter SELECT is much faster than before, up to 75% faster. - JDBC SELECT is about 10% faster than before. It’s still much slower than the native adapters, due to conversion issues. - bin/sequel now works with a YAML file on ruby 1.9. - MySQL foreign key table constraints have been fixed. - Database#indexes now works on PostgreSQL if the schema used is a Symbol. It also works on PostgreSQL versions all the way back to 7.4. - Graphing of datasets with dataset sources has been fixed. - Changing a columns name, type, or NULL status on MySQL now supports a much wider selection of column defaults. - The stored procedure code is now thread-safe. Sequel is thread-safe in general, but due to a bug the previous stored procedure code was not thread-safe. - The ODBC adapter now drops statements automatically instead of requiring the user to do so manually, making it more similar to other adapters. - The single\_table\_inheritance plugin no longer overwrites the STI field if the field already has a value. This allows you to use create in the generic class to insert a value that will be returned as a subclass: - When altering colums on MySQL, :unsigned, :elements, :size and other options given are no longer ignored. - The PostgreSQL shared adapter’s explain and analyze methods have been fixed, they had been broken in 3.0. - Parsing of the server’s version is more robust on PostgreSQL. It should now work correctly for 8.4 and 8.4rc1 type versions. ## Backwards Compatibility - Dataset#table\_exists? has been removed, since it never worked perfectly. Use Database#table\_exists? instead. - Model.grep now calls Dataset#grep instead of Enumerable#grep. If you are using Model.grep, you need to modify your application. - The MSSQL shared adapter previously used the :with option for storing the NOLOCK setting of the query. That option has been renamed to :table\_options, since :with is now used for CTEs. This should not have an effect unless you where using the option manually. - Previously, providing a block to a method calls in virtual row blocks did not change behavior, where now it causes a different code path to be used. In both cases, the block is not evaluated, but that may change in a future version. - Dataset#to\_table\_reference protected method was removed, as it was no longer used. - The pool\_timeout setting is now converted to an Integer, so if you used to pass in a Float, it no longer works the same way. - Most files in adapters/utils have been removed, in favor of integrating the code directly into Database and Dataset. If you were previously checking for the UnsupportedIntersectExcept or related modules, use the Dataset introspection methods instead (e.g. supports\_intersect\_except?). - If you were using the ODBC adapter and manually dropping returned statements, you should note that now statements are dropped automatically, and the execute method doesn’t return a statement object. - The MySQL adapter on\_duplicate\_key\_update\_sql is now a private method. - If you were modifying the :from dataset option directly, note that Sequel now expects this option to be preprocessed. See the new implementation of Dataset#from for an idea of the changes required. - Dataset#simple\_select\_all? now returns false instead of true for a dataset that selects from another dataset. Thanks, Jeremy - {Website}[[http://sequel.rubyforge.org](http://sequel.rubyforge.org)] - {Source code}[[GitHub - jeremyevans/sequel: Sequel: The Database Toolkit for Ruby](http://github.com/jeremyevans/sequel)] - {Bug tracking}[[Google Code Archive - Long-term storage for Google Code Project Hosting.](http://code.google.com/p/ruby-sequel/issues/list)] - {Google group}[[http://groups.google.com/group/sequel-talk](http://groups.google.com/group/sequel-talk)] - {RDoc}[[http://sequel.rubyforge.org/rdoc](http://sequel.rubyforge.org/rdoc)]