Sequel is a database 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, 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, DB2, DBI, Informix, JDBC,
	MySQL, ODBC, OpenBase, Oracle, PostgreSQL and SQLite3.

WWW: http://rubygems.org/gems/sequel3/